466 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxv. 



Young fondle — Two stages of development were obtained with the 

 adults. The youngest of these was only 3 mm. in length, and is 

 shown in fig. 111. The general structure is the same as that of the 

 adult, but the second maxillipeds here are twice the length of the 

 head and neck, and are entirely separate from each other for their 

 full length. Then they are attached close behind the first pair and 

 there is almost no interval between the two. The body posterior to 

 the base of the second maxillipeds is indistinctly segmented; there 

 are no posterior processes as yet, and the abdomen is very short and 

 rudimentary, ending in two conical anal laminae, each of which is 

 tipped with two short setae. 



In the second stage, 4.5 mm. iong, the second maxillipeds have 

 diminished in relative length and thickened considerably. There is 

 a greater space between the first and second maxillipeds, and the pos- 

 terior processes appear as short knobs on either side of the abdomen. 



Total length, 3 mm. Length of second maxillipeds, 1.85 mm. ; of 

 head, 0.8 mm.; of genital portion, 1.25 mm. Width of genital por- 

 tion 0.3 mm. 



Mule. — Body of the usual form found in this genus, with a hump 

 on the back opposite the maxillipeds and a constriction a little pos- 

 terior to the hump. The first antennae are relatively longer and 

 more distinctly segmented than in the female. The second antennae 

 are much narrower, but otherwise similarly formed; they do not, 

 however, bend around the anterior margin of the carapace, but stand 

 out from the side of the mouth tube parallel with the first pair. The 

 mouth tube is relatively much larger and embraces the whole anterior 

 portion of the cephalon, dorsal as well as ventral. The mouth open- 

 ing is terminal and surrounded by a fringe of hairs similar to that in 

 the female. Second maxillipeds adapted for prehension and, like 

 the first pair, armed with powerful claws. They are placed well back 

 from the mouth tube, and in side view appear near the center of the 

 body. Abdomen and anal laminae similar to those on the youngest 

 female. 



Total length, 1.0 mm. Length of head. 0.S nun.; of genital portion 

 behind the constriction, 0.7 mm. Width of body through the bases of 

 the second maxillipeds, 0.65 nun. 



Color. — Of preserved specimens a uniform snow white. 



((jnirilis, slender.) 



This species may be distinguished from others of the genus by the 

 length and slenderness of the second maxillipeds. by the fact that in 

 the adult they are held together for their entire length, though not 

 fused, and by the long abdomen, which resembles a fifth or odd 

 anterior process. 



