car and in a dory that had been carefully cleaned and partly 

 filled with water, and left floating so that the temperature would 

 remain something like that of the sea w^ter outside. At inter- 

 vals of a half hour up to midnight, the scallops in the car were 

 examined by lantern light and a little of the water in the dory 

 was examined microscopically, to see if eggs or sperm could 

 be discovered. As they were apparently not spawning, they 

 were left until just before sunrise, when observations were 

 again begun. About 8 A. M. sperm were discovered in the 

 water of the dory. Soon after several specimens began to throw 

 sperm in such quantities that the water in their vicinity was 

 turbid. Upon going to the car it was found that the water in 

 the car and for some distance outside was so full of eggs and 

 sperm that they could be dipped up in such numbers that the 

 bottoms of white agate ware dish pans filled with the water 

 became pink with the eggs that settled. The water was decanted 

 and the eggs supplied with fresh sea water. Some of the eggs 

 were transferred to glass dishes that were covered by loose 

 glass plates that prevented undue evaporation, and excluded dirt 

 that was rather in evidence in the shed on the steamboat wharf 

 that served as a laboratory. Water was changed in all of the 

 vessels at intervals during the time that the embryos remained 

 alive. 



The scallops that were put in the dory were removed as soon 

 as eggs were abundant, and after allowing a few minutes for 

 the eggs to settle, most of the water was dipped out and replaced 

 by pure sea water. The results were not satisfactory, however, 

 and as at 6 P. M. the embryos in the dory did not seem to be 

 doing well, not much further attention was given them. All 

 of them apparently died before those in the dishes were in bad 

 condition. This is not strange, as a large quantity of sperm 

 had to be left in the dory, and it was not possible to give the 

 embryos as good care in the bottom of a comparatively foul dory 

 as in the cleaner dishes. 



The development is what may be considered normal for lamel- 

 libranchs. There is no part of the early larval history that is 

 different from what might be expected for such a form, as it 

 differs very little from Teredo (9 and 27), Dressinia '(19), 

 Ostrea (4), Mya (18), Cardium, and a host of others that have 



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