THE OSTKACODA. 



259 



HALOCYPRID/E. 



CONCHCECIA AMETRA, Miiller. 



The specimens captured were unfortunately far too few to yield satisfactory means, 

 but three stages are clearly visible in both sexes. 



The actual observations were as follows : — 



Stage II. 

 Mean, 3-30, 



s. 



4 



Stage III. 

 Mean, 2-3. 



I' 



Stage IV 

 Mean, 1-42 



Table B 



.c 



mm. 



3-5 



3-4 



3.3 



3-2 



3-1 



30 



2-3 

 2-2 

 2-1 

 20 



1-6 

 1-5 

 1-4 



-Total specimens measured : 17 ? + 8 (? = 25. 



Taking an approximate growth-factor of 15 mm. for females and I'i for males, the 

 unknown Stage I. of this species would measure about 5*0 mm. in the female, and 4<'4 

 in the male. 



CoNCHCECiA BRACHYASKOS, Miiller. 



It would have been clear that there were at least two male and tAvo female stages 

 here, even if anatomical study had not shown them ; but the specimens Avero too few to 

 allow of any guess at their mathematical relations. 



The actual observations are as follows : — 



<J. 



Table C. — Total specimeus measured : 10 ? + (i J — Ifi. 



CoNCH(ECiA cuRTA, Lubbock. 



This species is by no means easy to manipulate ; it is very difficult to poise the almost 

 spherical shells in the protilo position which is necessary for accurate measurement and 

 drawing, and the shells are thin and readily distorted, i'urthcr, owing to its small size, 



SEOONB SERIES. — ZOOLOGV:, VOL. X. 



13 



