Stauber (1943) reports observations which suggest that sperm of Uro- 

 salpinx may remain viable in the female for extended periods of time . He 

 isolated an adult female collected in Delaware Bay from April 9 to October 21. 

 During this interval the snail oviposited 96 egg cases from which active young 

 drills were subsequently hatched in the laboratory. It is not known whether the 

 drill copulated in the early spring before capture or during the previous season, 

 but because of the low temperature of the water in April it is more likely that 

 copulation took place during the previous season. 



Ova 



Ova when first oviposited in the egg case are spherical in shape, average 

 0.36 mm. in diameter, and are yellow to orange in color. Reports on ova pro- 

 duction in the drill in different geographical areas are tabulated in Table 2 . 

 Stauber (1943) in the course of numerous careful measurements disclosed that, in 

 general, larger drills oviposit larger egg cases which in turn contain more ova 

 than do capsules of small drills: the average number of ova laid per egg case by a 

 16 . 5 mm drill was 4 . 7 and by a 29 . 6 mm . drill, 11.5. In addition the number 

 of ova per egg case seems to be influenced by unknown functional factors . Stauber 

 (1943) and Haskin (1935) independently describe instances where no ova were found 



TABLE 2 . Tabulation of the Egg Production in Urosalpinx cinerea in 

 Different Geographic Regions as Reported by Numerous Workers 



Number o| Ova 



Average per Range per 

 egg case egg case Region Source 



8,5 - Eastern Canada Adams, 1947 



10 5-17 Woods Hole, Mass. Pope, 1910-11 



8 4-16 Barnegat Bay, N .J . T.C.Nelson, 1922 



8 0-20 Barnegat Bay, N.J. Haskin, 1935 



8.1 ? Delaware Bay, N J ; Stauber 1943 



11 6-20 Chesapeake Bay, Va . Brooks, 1879(1880) 



8.8 3-22 Hampton Roads, Va. Fedenghi, 1931c 



11.7 1-29 England Cole, 1942 



_ 



