CRUSTACEA MALACOSTRACA. IV. I I 



Distribution. The type was taken off Portugal at Lat. ^8°y' N., Long. 9°i8' W., 550 fath. (G. O. 

 Sars). Caiman recorded it from a place off the Un. States: Lat. 40°i6'5o" N., Long. 67°05'i5" W., 1290 fath., 

 and from stations in the Mediterranean near Capri, 504 to 637 fath. 



7. Leucon spiniventris u. sp. 



(PI. I, tigs. 3 a— 3d). 



Female (adult and subadult). Allied to L. longirostris G. O. S., but very distinct. Carapace with 

 pseudorostrum about 4 times in total length; more than the posterior half of the dorsal crest is feebly curved, 

 nearly horizontal, while its anterior part curves gradually considerably downwards and is armed with 2 tri- 

 angular teeth very distant from one another, and the anterior somewhat behind the end of the frontal lobe; 

 the anterior tooth is moderately large, the posterior one considerably larger ; the lateral surface of the frontal 

 lobe without any tooth. Pseudorostrum is a little more than Vi of the total length of the carapace, directed 

 considerably upwards and tapering from near the base to the subacute end ; its upper margin has the posterior 

 half a little concave, while the lower margin has towards the base 2 distinct teeth and 1 rudimentary tooth. 

 The antennal notch is regularly and somewhat flatly concave without any incision or tooth. The antero-lateral 

 angle of the carapace is slightly produced and equipped with a strong tooth, behind which the lower margin 

 has about 12 teeth. The pleural plate of the antepenultimate thoracic segment has its infero-posterior angle 

 produced into a slender tooth turning downwards ; the last thoracic segment has on the anterior half of its 

 lower side two pairs of spiniform processes (fig. 3 c) directed downwards and forwards. The abdomen is rather 

 robust and a little longer than the cephalothorax ; its first segment has below a pair of procurved, spiniform 

 teeth (fig. 3 c). 



The antennuke are moderately long; second joint of the peduncle is very thick, third joint much more 

 slender, through still robust. The outer flagellum 3-jointed; first joint almost as long as the third joint of the 

 peduncle, and distinctly longer than second joint; the inner flagellum is a rather thick, subcorneal joint 

 with the end obtuse, and it is somewhat shorter than first joint of the outer flagellum. Third maxillipeds 

 without any conspicuous tooth on fourth or fifth joint. First thoracic legs without teeth on the lower side 

 of second joint ; the propodus is a little longer than the carpus and considerably longer than the terminal joint. 

 Second legs with the distal joints very robust; carpus nearly as long as the two following joints combined. 

 Fourth legs at least in the immature female (fig. 3e) with a spine directed forwards and somewhat upwards 

 on the antero-interior side of second joint somewhat from its base. - - The uropods (fig. 3d) are a little 

 shorter than the two distal abdominal segments combined. The peduncle in the adult with about 7 spines 

 on its inner margin. The endopod is as long as the peduncle; its proximal joint at least five times as long as 

 the distal joint which terminates in a strong, somewhat curved spine longer than the joint; this distal joint has 

 4 or 5 spines on its inner margin, while the proximal joint has in the adult about 17 spines; among the 8 

 spines on its distal fourth 3 are long and strong, while 5 are rather short; in the immature specimen 14 or 

 15 spines were observed on the proximal joint. The exopod is considerably shorter than the endopod. 



Length of a female with brood in the marsupium 7 mm. 



