NO. 3594 SARSIELLA — KORNICKER 31 



Reproduction. — Eggs were observed in the ovary of 1 pre-adult 

 (stage V) female. Since the genitalia of the stage V females were not 

 completely developed, however, we can conclude that eggs are prob- 

 ably not fertilized at this stage. Apparently eggs remain in the ovary 

 of the pre-adult until the adult stage when the posterior of the adult 

 shell broadens to accommodate the eggs. 



Most gravid adult females in the collection have 10-11 eggs in the 

 brood chamber but the observed range is 5-16. Some specimens have 

 eggs botli in the ovaries and brood chamber. Embryos with well- 

 developed appendages were observed in only one specimen. Jones 

 (1961, figs. 20d-f) reported that at least 55 percent of adult females 

 in collections made throughout the year off Point Richmond, Calif., 

 contain either eggs or embryos. 



Prior to molting it is often possible to observe the new appendages 

 and valves inside the old. About 20 adult females with eggs in the 

 brood chamber were examined but no indication of post-adult molting 

 was observed. 



Ecology. — Water depth : Specimens of S. zostericola w^ere collected 

 in the Hadley Harbor area at depths of not more than 6 m. Blake 

 (1933, p. 230) collected S. zostericola from along the coast of Maine 

 at depths of 1-22 m, but specimens were sparse at 22 m. Specimens 

 of S. zostericola from the Texas coast were collected in 1-2 m of water 

 (Kornicker and Wise, 1962). In the Point Richmond area, Calif., 

 S. zostericola was collected at depths of 2-11 m (Jones, 1954.) The 

 tabulation below from data in Jones (1954) shows that ostracod 

 abundance decreases markedly at depths below about 6 m (20 ft). 



The distribution of S. zostericola at various depths in the vicinity of 

 Point Richmond, Calif., is as follows (Jones, 1954): 



Temperature and salinity: In the Point Richmond area, Calif., S. 

 zostericola was collected at temperatures from 17.2°C to 18.8°C and 

 salinities from 22 to 30%o (see tabulation on p. 32). Along the coast 

 of Texas specimens were collected at temperatures from 16.2°C to 

 25°C and salinities from 20 to 36%o (Kornicker and Wise, 1962). 



Substrate: Specimens of S. zostericola were collected in Hadley 

 Harbor in sediment with a median diameter of 60 microns and sorting 

 index (SO) of 2.5 (Nagle, in litt., 1965). In the Point Richmond 

 area, Calif., S. zostericola was collected from grey to black muds com- 

 posed of more than 64 percent of particles in the fine sand to clay 



