i(j4 lldibic Molhisca of the Orcs^^on C (nist 



111) artiviU' at this time. ( )ii Jul)' 22n(l. ImwcviT. lliere was evi- 

 dence ihal the si)ecies was in the midst of the s])a\\nini4- season. 

 Spermatozoa were well tOrmed. mature and very active. As in 

 case ot' man\' other clams, ova niay he detected in tlu' females at 

 an\- period of the vear : on July Jjnd. hiiwever. the\ were very 

 lari^'e and well rounded, their maturitx' evident]}' corresponding' 

 with the maturit\ of the s])ermati izoa. ( )n examining males and 

 females Sei)teml)er 4tli it was ohserved that the hodies of hoth 

 were s])ent, indicating- that the spawning- season was past. 



After ha\inL;' examinetl the ovaries and spermaries of the 

 razor clam throuL^hout several successive }ears, it ma_\' l)e safely 

 concluded that the species on the heaches of Clatsop County, 

 ()reg'on. bei^ins >])awnini;- in the earl\- summer, prohahl)- about 

 lune 1st. and continues t]irou,i.;iiout jul\' and AuL^ust (Figure \. 

 1. 2. 31. 



There are reasons to believe, however, that the period of 

 s])awning ma)' vary somewhat from year to year. On September 

 4th. i(;i8, of the small razor clams found in the sand there were 

 few under 30 mm. in length of shell, ])rol)al)l_\' indicating a rela- 

 tively early summer s]xiwning' for the species. On September 

 15th, 1919, however, small clams ranging from 8 to 20 mm. in 

 length were very abundant, which may indicate a dilTerence in 

 the growing conditions during tile two summers or that the 

 spawning season was somewhat later in 1919 than in the preced- 

 ing )ear. 



2. Schizothaerus nuttalli Conrad. 



Microscopic examinations of the ovaries and spermaries of 

 the "Washington clam," conducted during the summer, winter and 

 spring months, indicate that the spawning season of the species 

 on the Oreg'on coast takes i)lace during Februar\' and March 

 ( Fig-ure A', 4, 5, 6 ) . 



Early in Februar}' well developed spermatozoa begin to appear 

 in the spermaries with some activit}' noted. On Afarch 26th. 1918, 

 spawning was still in ])rogress. the bodies of both males and 

 females being well filled with the sex elements, the spermatozoa 

 showing great aclivitv and the ova evidentlv in a state of matur- 



