1913] EsterJy: Copcpoda of the San Diego Begion 183 



5, 27). The genital segment has a characteristic form (pi. 10, 

 figs. 5, 27) ; it is not symmetrical ; the ventral surface is markedly 

 protuberant, with a lamella at the right of the orifice. The figures 

 give a better idea of the form of the segment than is possible in 

 a description. 



The anterior antennae are slightly longer than the cephalo- 

 thorax. In the second foot, the outer marginal spine on the end 

 of the second joint of the outer ramus reaches nearly to the tip 

 of the first spine of the last joint ; the middle spine of the third 

 joint is long and extends to the distal margin of the joint, but 

 the proximal and distal spines are short (pi. 11, fig. 37). The 

 outer ramus of the first two (pi. 12, fig. 49) is 2-jointed, though 

 there is some indication of the suture between the first and second 

 joints; the outer margin of the proximal division of the ramus 

 is deeply concave and bears one spine, which reaches to the end 

 of the distal division. 



Length: 4.13 mm. (cephalothorax 2.95 mm.). 



Coloration : Tran.slucent and whitish in formalin. 



Occurrence : Haul 2258. 



Onchocalanus latus Esterly 



PI. 10, iigs. 33, 15; pi. 12, fig. 58 



Drawings are given here to supplement those previously shown 

 (see Esterly, 1911, p. 326). It is certain that this species does 

 not possess a fifth pair of feet, though I stated in the passage 

 just cited that it was lost through mutilation ; the specimen 

 described as 0. latus meet the description of Onchocalanus as 

 given by Sars (1905a, p. 18) and by Farran (1906, p. 49) in 

 important requirements notwithstanding the absence of the fifth 

 pair of feet. 



The animal figured in this paper was 4.3 mm. in length and 

 was taken in haul 2134. 



Scolecithrix aculeata n. sp. 



PI. 10, figs. 2, 25; pi. 12, figs. 63, 64 

 Adult female. The head is rounded and further characterized 

 by the bifid rostrum, each prong of which is heavy at the base 

 and carries a delicate but stiff and sharp spine at the distal end 



