5K> BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



to the base of the insertion of the pleopods. The last segment of the 

 abdomen ^ bears only two uropods, of the same conformation as the 

 pleural lamella? and the outer branches of the pleopoda of the preced- 

 ing segments, but the}' are of a length exceeding the longest of these 

 appendages. Turned back and laid on the dorsal surface, they extend 

 to the middle of the thorax. 



The male, unknown in the other species of the genus, recalls a great 

 deal, in its general form, that of the genus Cancricepon. It measures 

 in its greatest dimension 0.55 mm. The first antennas are composed 

 of three articles, the second antennae of five articles, the most of 

 Avhich are furnished with stiff hairs; there are no maxillipeds. In 

 the median line of the thorax are spherical tubercles which are also 

 present in the same place on the first three segments of the abdomen; 

 their external surface is covered witli little pectinate scales. The legs 

 are short, robust, and terminate in a pointed claw. The genital open- 

 ings are visible on both sides of the ventral tubercle of the seventh 

 thoracic segment, and in a clear area lighter than the rest of the 

 cuticle. Rudiments of pleopods are seen on the first five segments of 

 the abdomen, and the uropods are represented on the sixth segment 

 only by two little bunches of stiff hairs. 



In general there is but a single adult male on a female; I ought, 

 however, to note as rather frequent the presence of several males on 

 the same female; I have counted just four of them between the pleo- 

 pods and the pleura, and, a curious thing, all of them having abso- 

 lutely the same form, they do not have the same size. One of them 

 was a little more than half the size of the largest, the other two were 

 of intermediate size. The ventral bosses appeared in the three indi- 

 viduals of smaller size on the five segments of the abdomen, while in 

 the largest specimen they actually were present only on the first three. 

 It is probable that the number of these bosses decrease with age. The 

 same fact is equally true of Cancricepon eleyans." 



The above description is adapted from the following one of Bonnier's: 

 La femelle adulte a une forme generale globuleuse, aplatie sur la surface dorsale 

 et terminee a son extremite posterieure par un bouquet d' append ices ertik's a bords 

 digites; elle mesure, du bord frontal au sixieme somite du pleon, 1 mm., 9. La tete 

 forme une masse unique et saillante qui est entouree anterieurement et sur les tutt's 

 par une large lame ant^rieure flottante; a la face interne se trouvait, a une assez 

 grande distance, 1'une de 1'autre, les antennules tres petites et tri-articulees; les deux 

 derniers articles portent quelques petites soies et leur surface est squameuse; les 

 antennes sont egalernent courtes, le premier article est large, A, moitir soiulr au rt'pha- 

 lon et les quatre autres articles diminuent d'importance jusqu'au dernier qui portc 

 quelques soies; leur surface presente le meme aspect que celui de 1'antennule. Le 

 rostre est preeminent et particulierement net; de la pointe echancree de la levre infe- 

 rieure on voit sortir 1' extremite des mandibules qui est en forme de cuilleron & bord 

 finement denticule. Le maxillipede possede un palpe allonge termine par de petites 

 soies tree courtes. Le bord inferieur du cephalon est decoupe" de part et d'autre par 





