494 Astacilla longicornis. 



Body of a pale yellow colour, dusked about the middle, 

 linear, posteriorly tapered a little to the anus, rounded dor- 

 sally, smooth, glossy : head chestnut-brown, quadrangular, 

 narrower than the post-occipital segment, punctured all over, 

 and sparingly hispid on the sides : the inferior lip punctured, 

 divided by a medial line : maxillae strong, with blackish- 

 brown claws : antennae originating in the anterior margin, 

 tapered, hairy, with 14obconical yellow joints, deeper-coloured 

 at their apices, the basal one short and stout, second, third, 

 fourth, and fifth twice as long, the following shortening insens- 

 ibly to the terminal, which is again longer and elliptical : 

 post-occipital segment brown, lunate, the lateral angles em- 

 bracing the lower half of the head : segments shorter than 

 their breadth, dusky along the posterior margin, marked with 

 two impressed lines, interrupted by the narrow interstitial 

 segments, which are mammillary on the sides: the ventral 

 surface flat, of the same colour as the dorsal, with a roundish 

 depression in the centre of each segment, and an impressed 

 line along the sides: legs uniform, hispid, the posterior pair 

 longer. Length, I J in. ; breadth, 1 line. When viewed 

 sidewise, a few very short hairs are seen scattered over the 

 back ; and a series of pores are visible along each side, one 

 to every segment. 



Art. IV. Illustrations in British Zoology, By George John- 

 ston, M.D., Fellow of the Royal College of Surgeons of Edin- 

 burgh. 



43. Astaci'lla longico'rnis. (fig. 44.) 



Synonyma. — Oniscus longicornis Sowerby, Brit. Misc., tab. 15.; Penn., 

 Brit. Zool., iv. 42. Leada lacertosa Johnston, in Edin. Phil. Journ., 

 xiii. 220. Astacilla longicornis Fleming, in Encyclop. Brit., vii. 502. 

 edit. 7th. 



Description. — Body linear, subcylindrical, lj in. long, 

 cinereous with dusky spots or blotches, granulous and tuber- 

 culate, formed of seven very unequal thoracic and two 

 abdominal segments : head larger than the following segment, 

 deeply lunate in front, the projecting angles obliquely trun- 

 cate, the vertex flattish, tuberculate, and impressed, con- 

 stricted behind the eyes, which are lateral, prominent, round, 

 black, and reticulated : antennae four, frontal, approximate at 

 the base ; the superior very short, four-jointed, the basal 

 joint bulbous, the two next short, nearly equal, the terminal 

 one elongate, linear-elliptical, ciliated along the under side 

 with curious pedicled tubular hairs ; inferior antennae nearly 



