ARTICLE VIII. — An American Terrestrial Leech. By S. A. Forbes. Our common land leech was first obtained by me in April, 1876, at Normal, McLean County, Illinois, where it was dug up in a house garden, about a dozen rods from the nearest rivulet. An example sent the following year to Prof. A. E. Verrill, with some remarks on its superficial characters, was by him iden- tified provisionally and with some hesitation as his Semiscolex grandis, originally described* from three aquatic individuals obtained from Lake Huron, Lake Superior, and West River, Connecticut. I have now, however, fifty-six specimens of this leech, all from the earth in Central Illinois, some of them half a mile or more from water, and representing collections made at different times from April, 1876, to June, 1890 ; while, on the other hand, it has not once occurred in the course of a large amount of aquatic work done in the same regions during these fifteen years. It has, moreover, constant characters which clearly distinguish it from Semiscolex qrandis^ as far as one may judge by a comparison with VerrilFs description, and I do not doubt that it is distinct. Its only known food is earthworms of various genera, and these it swallows entire, as I have repeatedly found by dissec- tion, and demonstrated likewise by feeding experiments on leeches in captivity. From the fact that all my specimens were obtained during the early months of the year,— from March to June,— it is probable that this leech, like the earthworm, penetrates to considerable depths during the midsummer drouths. DIAGNOSIS. Semiscolex terrestris, Forbes.f This is one of the largest of our leeches, my contracted alcoholic specimens reaching a * {Synopsis of the North American Fresh Water Leeclies. By A. E. Verrill. U. S. Commission of Fish and Fisheries. Part II. Report of the Commissioner for 1872 and 1873, p. 072. t American Naturalist, vol. xxiv., 1890. 120 Illinois State Laboratory of Natural History. length of seven inches, a width of three fourths and a depth of three eighths of an inch. In form, it is heaviest pos- teriorly, being widest at about the eighth annulus. in front of the acetabulum, but tapering very gradually or scarcely at all thence forward to the anterior fourth, and thence more rapidly to the mouth. Its transverse sec-tion is depressed oval, flattened beneath, the margins of the body obtuse. The color is sooty drab, varying to plumbeous black, some- what lighter beneath, uniform in tint, and quite without spots or mottlings of any sort. A darker median longitudinal stripe, very conspicuous and well defined, is almost invariably present ; a paler marginal stripe often approaching buff, little less con- stantly so; and a ventral submarginal stripe of the same color as the median dorsal one likewise quite frequent. The surface is everywhere smooth, and I find no external trace of segmental papillae. There are ninety-nine complete annuli from the mouth to the posterior sucker, four imperfect aunuli in the cephalic lobe (counting the one bearing the first pair of eyes as the first), and one such just before the vent— one hundred and four in all. All the perfect annuli are very distinct except the first two, which, while well distinguished dorsally, are almost, but not quite, fused beneath to form the posterior border of the mouth. In front of the first annulus is the upper lip, divided by a delicate median groove. There are, consequently, eleven such grooves meeting the margin of the mouth, its posterior boundary being formed by the undivided ventral portion of the fifth annulus. The eyes are ten in number, placed upon the first, second, third, fifth, and eighth annuli, representing somites one to five. The acetabulum is broad oval, wider than long, and measures about 10 mm. in its greatest diameter. The vent is large and surrounded by irregular radiating grooves. The first nephridial pore is at the anterior uiargin of the tenth complete annulus,— the fourteenth in all,— and the last or seventeenth pore at the anterior margin of the ninetieth vent- ral annulus,— the ninety-fourth of the full series. These pores open on the ventral surface just within the dark ventral line, and consequently at some little distance from the margin of the body. The male sexual opening is on the posterior part of the An American Terrestrial Leech. 121 twenty-eighth entire annulus and the female opening on the thirty-third. Within the buccal cavity is a prominent circular fold. Maxillse three, minute, .5 mm. to .66 mm. in length, each with an armature of twelve to fifteen bicuspid teeth. The pharynx presents ten to fifteen longitudinal folds, the number varying in different parts, with an average of twelve or thirteen. I have seen no specimens of Semiscolex grandis, Verrill, but draw from the author's description distinctions in the number of the annulations ( " about ninety" in fjrandis ), the presence of maxillae, the positions of the sexual orifices (in grandis in the twenty-fifth and thirtieth annuli respectively), and in the color markings, — grandis being, in Verrill's speci- mens, without stripes, but spotted or blotched with dark. ANATOMICAL NOTES. The genus Semiscolex, to which this species unquestionably belongs, was described by Kinberg* in 1867, but has been since very little discussed. It is not, in fact, again referred to in any literature within my reach, except by Verrill, in the third volume of the American Journal of Science (1872^ p. 136, and in the Report of the U. S. Fish Commissioner for 1872 and 1873, p. 671. It is clearly closely allied to Aulastoraa, Moqu., and seems to me but doubtfully distinct. The following anatomical details will help to an understanding of the rela- tions of our species : The alimentary canal is clearly distinguishable into five regions. The first is the pharynx (closely invested by muscles), which extends to about the twenty-second annulus from the mouth. The second is the so-called oesophagus and proventric- nlus, a simple cylindrical tube without lateral sacculi, ter- minating opposite the fourteenth ventral ganglion (counting the sub(L'sophageal as the first), where it gives off two long, slender sacculi which extend backward beside the alimentary canal to the last testis. At the point of origin of these sacculi, the canal becomes very much enlarged, the three remaining * Ofversigt af Kongl. Vet. Akad. Forhandlingar, xxiii, p. 357. 122 Illinois State Lahoratory of Natural History. divisions being of nearly equal length. The third region, the digestive stomach of Bourne, is large and thin-walled, its cavity presenting about four regular constrictions, and its mucous membrane being conspicuously and finely rugose. The next section, the intestine proper, is smaller, with minute, irregular, and much less conspicuous rugosities ; while the last section, the rectum, is about the diameter of the stomach, with a smooth mucous membrane. It passes backward without nar- roAving, rapidly rounding directly into the large anus. The testes are ten in number in the specimens examined. The penial sheath is very long, extending from opposite the seventh ventral ganglion (where it is surrounded by the glandnla prostatica) backward to a point opposite the ninth ganglion. Here it bends abruptly forward upon itself and passes to its external opening beneath the sixth ganglion. Immediately in front of the glandnla prostatica lies the glandular part of the seminal vesicle of the left side, that of the other side being just opposite. Forward from this runs the thick-walled, shining ductus ejaculatorius, continued pos- teriorly as a slender, somewhat contorted tube which meets its fellow of the right side as this tomes under the nerve cord just behind the sixth ganglion, the two then running in company to the base of the penial sheath. The ovaries are small, nearly spherical, and lie closely approximated on each side of the nerve cord, immediately be- hind the seventh ganglion. The common oviduct passes first through a pyriform glandnla albuginca, the apex of which reaches backward to the eighth ganglion, and then, at first small but presently much enlarged, runs backward somewhat deviously to the ninth ganglion, where it turns directly forward and continues unchanged to its orifice. The sub( esophageal ganglion is closely approxiniated to the next behind, the second and third ganglia are about half as far apart as the third and fourth, and these about two thirds the distance of the fourth and fifth. The last four ganglia are likewise much approximated, the posterior one being very large, and sending off several pairs of branches. ERRATA.* Page 47, line 6, page 4H, line S, and page 4i», lines o, <), and lo Ironi bot- tom, for clifi'llus read cliteUKm. Page Tit, line 9, for OpUouea read Opilionea. Page 108, line 11, for longitudinal read circular. Page lOit, line S, for ivorms read body. Page 115, line 1, dele initial 11. Page 122, line 10, for ten read twenty. Page 13S, line Ki, for lUackisded read Black-sided. Page 185, line 13 from bottom, page 228, line 17, and page 229, line 7 from bottom, for tvoonti read troostii. Page 187, line 12 from bottom, page 272, line fi from bottom, and page 275, line 1, for kirtlandi read kirtlandii. Page 187, line 15 from bottom, for lineata read lineatum. Page 218, line 17 from bottom, for 7 read .7. Page 214, line 7, for 7 and 3 read .7 and .3. Page 224, line 13 from bottom, for Tortoise read Tortoises. Page 225, line 3, for jiicta read marginata. Page 240 line H from bottom, for 1S24 read l'S25, and before pp. insert IV. Page 242, line 8 and 12 from bottom, and page 243, line 1, tor Macro - clenn/s read Macroclemmys. Page 252, line 11, for Crematogaster read Cremastogaster. Page 269, line 22 from bottom, and page 271, line 1, tor fasciatiis read fasciata. Page 272, line 9 from bottom, and page 273, lines 7 and 14 from bottom, for grabami read graliamii. Page 293, line 13 from bottom, for elapsoidea read elapsoidens. Page 295, line and line 3 from bottom, for auKmus read anuvna. Page 349, line 3 from bottom, for A read W. Page 352, line If), for Icthyomorpha read Ichthyoniorpha. Page 353. line 4 from bottom, for Menopomidw read Cryptobranchidce . Page 3t)(i, line It), and page 3B7, line 14 from ho\Xon\, tor erythronoto read erythronotus. Page 31)7, line 8 from bottom, for relations read relation. Page 371, line 11 from bottom, for eingulata read cingatatnm. Page 378, line 7, dele period after prehension. S. Garman is antliority for last sentence of paragraph only. Page 385, line 4 from bottom, dele comma after its. Page 410, line 18 from bottom, for suhlata read suhidaia. Page 411, line 11, for hrmalmlata read bimaculata. Page 431, line Itifrom bottom, for nmtica read mnticHs. Page 435, line 12 froni bottom, for t/uerci read (juercHs Page 441, line 19, for Salamandra read salamandnt. Page 451, line 14 from bottom, for Anonophom read Aronopliora. Page 4S(), line 4, for liinahta read limbata. Page 494, line 2 from bottom, and page 195, lines 13 and HI, lor lineattis read lineata. *See also pp. 17s is] of Article Xl\ . ADDENDA AND ERRATA. To coiiiplete the list of species recogiii/.cil by St«•-)) 480 Illinois iState Laboratory of Natural History. Page 400, between lines IJ and 10 insert as follows: 1851. Cyphonia redispina. Walk. List Horn. B. M. 597, 6; line 19, for postfaciata read posffasciata. Page 401, line 4, for huhalus read diceros. Page 402, at bottom of page add as follows: 1891. Ceresa huhalus. Fletcher, Rep. Ent. and Bot. Can. 191. 1892. Ceresa huhalus. Osb. Trans. la. Hort. Soc. 119, fig. 30. 1893. Ceresa biihalus. Osb. Fruit and Forest Tree Ins. 24, fig. 80. Page 403, line 21, for the interrogation point substitute a period; between lines 2 and 3 from bottom insert as follows: 1892. Ceresa taurina. Osb, Trans. la. Hort. Soc. 119. 1893. Ceresa taurina. Osb. Fruit and Forest Tree Ins. 24. Page 409, between lines 4 and 5 from bottom insert as fol- lows: Stictocephala gillettei, $. Godg. Ent. News, iii, 200. Page 411, line 2, for nigripes, Stal, read numda, Walk.; be- tween lines 2 and 3 insert as follows : 1858. Parmula munda. Walk. List Hom. B. M. Suppl. 152; line 4, for Mex. {Stdl), read Mex. and Guatemala ( Walk.). Page 412, between lines 11 and 12 from bottom insert as follows : 1892. Thelia cratwgi. Osb. Trans. la. Hort. Soc. 119. 1893. Thelia cratcegi. Osb. Fruit and Forest Tree Ins. 24. Page 413, line 12 from bottom, and page 414, line 1, for acuminata read acuminatus. Page 414, line 11, for Hyphina read Hyphinoe. Page 416, line 8 from bottom, for Telamona read Mem- bracis. Page 417, line 1, for 1841 read 1851. Page 422, between lines 8 and 9 insert as follows : 1892. Telamona niexicana? Godg. Ent. News, iii, 108. Page 424, line 9, for toj) read tips. Described Memhracidce of North America. 481 Page 425, line 6, dele " fig." ; line 2 from bottom, for galata read gahata. Page 427, line 4 from bottom, ior Membracis read Acutalis. Page 429, line 15, after '' lower " insert edge. Pages 435 and 436. Note.— An examination of the types shows that numbers 122 to 126 belong to Cyrtolobus. Page 437. After the numbers 128, 129, and 130, for A. read E. * Page 441, line 17 from bottom, for V. read Ama&tris'\; line 4 from bottom, insert (?) before V. Page 442, between lines 8 and 9 insert as follows : 1851. Thelia exjjansa. Walk. List. Hom. B. M. 563, 26; between lines 14 and 15 from bottom, insert as follows: Thelia mar- morata. Walk. List. Hom. B. M. 555, 4. Page 444, line 15 from bottom, after "scar" insert as fol- lows: Apical cell much longer than in marmorata, the length ex- ceeding the breadth more than twice, while in marmorata the cell is but a little longer than broad; line 14 from bottom, after '' fuliginous" and '"yellow" substitute semicolons for commas; line 7 from bottom, after " process," add as follows: in not being suddenly depressed a short distance before apex, in not having the median carina flat from this depression, and in being much more depressed anteriorly. Page 445, line 8. Note.—Through the kindness of Rev. W. W. Fowler, of Lincoln, England, I have had the opportunity to examine St3,rs type of the genus Optilete, and, as surmised, it proves to be a typical marmorata, Say. Between lines 16 and 17 from bottom insert as follows: 1851. Hemij)tycha longicor- nis. Walk. List Hom. B. M. 569, 7. Page 449, line 10 from bottom. Note.— Walker's Darnis lineola belongs to Phacusa {Fide Fowler). Page 452, No. 181, for prunitia, Butler, read hastata, St4l (A*c?e Fowler). * Ashmeadea being preoccupied, the name was changed to Ev- ashmeadea. t A more careful study of the species places it in Amaatris.