A history of the British sessile-eyed Crustacea . last segment of the body. The terminalsegment is also narrowed at its base; and if we draw aline from its outer basal angles to the lateral angles ofthe two basal segments, we shall perceive that the lateralmargins of the third, fourth, and fifth segments are pro-duced outside of this line, and are strictly supplementalappendages or lateral lobes. The extremity of the terminal segment is producedinto a narrow and elongated point, its upper surfacebeing convex, the basal portion of the terminal appen-dages extending to about half the length of t
A history of the British sessile-eyed Crustacea . last segment of the body. The terminalsegment is also narrowed at its base; and if we draw aline from its outer basal angles to the lateral angles ofthe two basal segments, we shall perceive that the lateralmargins of the third, fourth, and fifth segments are pro-duced outside of this line, and are strictly supplementalappendages or lateral lobes. The extremity of the terminal segment is producedinto a narrow and elongated point, its upper surfacebeing convex, the basal portion of the terminal appen-dages extending to about half the length of this pro-duced joint, of which the apex reaches the middle ofthe outer division of the appendage; the inner lobe ofthe basal portion is narrow and elongated, extending ashort distance beyond the extremity of the tail. The species frequent damp situations, and have notthe power of rolling themselves into a perfect ball, butattempt to do this in an incomplete manner, feigningdeath when alarmed. H Fi i: 468 ONISCIDJl. ISOPODA. NORMA LI A. ONISGID^:.. ONISCUS ASELLUS. S2)ecific character. Broadly ovate, sub-depressed, shining ; covered withsmooth granules. Lateral lobes of the cephalon large, inclined line somewhat emarginate. Terminal segment of the pleon elongate-triangular, convex above. Intermediate segments of the pleon terminatingin acute angles. Length, three and a half to eight lines. Oniscus asellus. Linn., Syst. Nat. ii. p. 1061. De Geer, Ins. vii. t. 35,f. 1. Geoffroy, Ins. Paris, ii. t. 22, f. 1. Latreille,Hist. Nat. Crust, et Ins. vii. p. 42. Leach, Edin. 406. Samouelle, Ent. 111. Johnsson,Syii. Framst. Sver. Onisc. p. 15. White, B. M. Crust, p. 71. Pop. Hist. Brit. Crust, p. 234. Oniscus muraritis. Cuvier, in Journ. dHist. Nat. ii. t. 26, f. , Ent. Syst. Suppl. p. 300. Brandt andRatzeb., Arzn. Thiere, ii. t. 12, f. 7. Brandt, inBull. Mosc. vi. p. 182. Milne Edwards, Crust, iii. ONISCUS ASELLUS. 469 p. 163. KiN
Size: 1689px × 1479px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthor, bookcentury1800, bookdecade1860, booksubjectcrustacea
