ISOPODA OF THE 'LIGHTNING' AND OTHER EXPEDITIONS. 129 



carpus subquadrate ; propodos rather longer than carpus, parallel-sided, with one infero- 

 distal spine ; dactylus large, longer than propodos, unguiculate. 



The last segment of the perseon in the type specimen has no legs, nor can we see any 

 sign of scars where they would have been attached, and the specimen was otherwise 

 quite perfect. 



Uropods (fig. v. pi.) with both branches narrowly lanceolate, equal-lengthed, and 

 tipped with tufts of setse ; outer branch over the inner, very narrow, showing no 

 tendency to arch over the back, as is usual in the genera Anthura and Paranthura, 

 nearly parallel-sided, with a narrowly rounded apex; inner rather wider than outer, but 

 also narrowly lanceolate, its inner margin straight, the outer margin sloping away near 

 the apex to meet it; first joint short, second nearly three times its length. 



Telson very narrow, elongate-lanceolate, apex acute and terminating in a little tuft 

 of setse, otherwise perfectly smooth and glabrous. 



Length about a quarter of an inch ; the form very narrow in proportion to its 

 length. 



A single specimen, dredged in the North Atlantic by H.M.S. 'Valorous' in 1875 

 (Station No. 11, lat. 56° 11' N., long. 37° 41' W., in 1450 fathoms.) 



Genus 5. Paranthura. 

 1. Paranthura nigro-punctata (Lucas). (Plate XXVI. fig. n.) 



1840. ? Anthura gracilis, M.-Edwards, Hist, des Crust, iii. p. 136, pi. xxxi. fig. 3 (probably; but 



not A. gracilis, Mont.). 

 1846. Anthura nigropunctata, Lucas, Explor. Scient. de l'Algerie, Anim. Artie, p. 64, pi. v. fig. 9. 

 1866. Anthura nigro -punctata, Heller, Verhandl. d. k.-k. zool.-botan. Gesellschaft in Wien, 1866, 



p. 732. 

 1866. Paranthura costana, Bate and Westwood, British Sessile-eyed Crust, ii. p. 165. 

 1870. Paranthura costana, Dohrn, Untersuchungen ii. Bau und Entw. der Arthropoden (erstes 

 Heft), 1870, p. 91, pi. ix. 



Perseon smooth above (neither keeled nor pitted), the first six segments subequal in 

 length to each other ; body narrowed at the hinder portion of the first and second 

 perseon-segments ; last segment about half the length of penultimate. 



Pleon distinctly segmented, portion anterior to the telson equal to penultimate 

 segment of perseon. 



Telson linguiform. Uropods wide apart above, scarcely at all arching over telson ; 

 outer branch small, narrow, lanceolate, shorter than inner ; inner as long as the telson, 

 its second joint as long as the first ; both telson and uropods are setose, especially at 

 their terminations. 



Eyes very distinct, black. 



