2 I 



to it a small acute spine directed outward ; the lower borders of this somite end in an acute 

 tooth and one observes, close to the latter, though already on the lower surface of the somite, 

 a small spine, which is directed backward and placed near the posterior margin (Fig. je). 

 Concerning the telson (Fig. 7 ƒ and jg), which in the adult female is 5 mm. long (without 

 the terminal spines), I have remarked in my description of 1902 that the upper surface was 

 armed with three pairs of spines and the tip with four: this was not quite right, for the tip 

 is armed with five pairs. Of the 3 pairs of spines on the upper surface the anterior is situated 

 in the adult female near the base, at about Yb °f tne entire length distant from the proximal 

 extremity, the two spines are implanted near the middle line, 0,5 mm. long and 0,36 mm. 

 distant from one another; the 2 nd and the 3 rd pair are implanted close to the margins of the 

 telson, the 2 nd pair situated at the anterior third and 0,44 mm. long, those of the 3 ld pair 

 just behind the middle, at 29 /so °f tne length from the base, and these spines are 0,42 mm. 

 long. The median spines of the posterior extremity i. e. those of the i st pair, are 0,54 mm. 

 long, those of the 2 nd pair 1,4 mm., the longest of all, those of the 3 rd pair 1,16 mm., the 

 spines of the 4" 1 pair, implanted just in front of the 3 rd , are 0,55 mm. long, the spines of 

 the 5" 1 pair, finally, are those that were overlooked by me in 1902; they are implanted between 

 the 2 nd and the 3 rd pair, are slightly bent inward, 0,58 mm. long, reach hardly beyond the 

 truncate extremity of the telson and are armed on both margins with similar small denticles 

 as occur also on the inner margin of the other spines. 



The peduncle and the longer (outer) flagellum of the inner antennae measure together, 

 in the adult female, about 21 mm., being about 3-times as long as the carapace, when measured 

 in the dorsal median line (j 1 /^ mm.), while the outer flagellum is twice as long as the carapace: 

 according to Stimpson the antennulae should be hardly longer than the latter. The scaphocerite 

 of the adult female is 4 mm. long and 3 1 / 3 -times as long as wide, presenting the greatest width 

 at the posterior fourth or hfth; it has an elongate triangular form and, gradually narrowing 

 distally, ends in a sharp spine, that is 0,18 mm. long. 



The mandibles are broad, flat, though slightly concave; their margin, which is not 

 deeply cleft like in Lept. gracilis Stimps., is armed with 12 or 13 teeth that from before 

 backwards decrease in size; the 5 or 6 anterior teeth are considerably larger than the rest, 

 their form is somewhat variable and sometimes even difters in the two mandibles of the same 

 individual, as in the two of the adult ova-bearing female from Stat. 153, figured Fig. ~/i 

 and j/i'. In the right mandible of this specimen the 2 nd tooth is the largest of all and bears 

 a secondary denticle at the base of its posterior margin ; the 3 rd and the 4 th are subequal, 

 smaller than the 2 nd , a little larger than the i st ; the 5" 1 and the 6 th are also subequal and 

 only half as large as the two preceding, the following small teeth regularly decrease in size. 

 In the left mandible the 2 nd tooth is also the largest of all. but bears no secondary tooth: 

 the i st tooth is but little smaller than the 2 nd , the 3 rd only half as large as the i 5t , the 4 ,h 

 almost of the same size as the i st , little smaller, the 5 th nearly of the same size as the 3" 1 , 

 while the remaining small teeth regularly diminish in size. In a male specimen from the same 

 Station the i st tooth bore a small denticle on its outer margin and was of the same size as 

 the 4 lh ; the 2 nd was twice as large, the largest of all, the y d a little smaller than the i st , the 



