THE LARVA AND SPAT OF THE CANADIAN 

 OYSTER 



J. STAFFORD, M.A., Ph.D. 

 McGill University 



n. The Spat 

 In the first part of this article, dealing- with the larva, 1 

 I have already indicated that, in the progress of my re- 

 search, it soon became necessary to plan means of pro- 

 curing young oyster spat for comparison with my sup- 

 posed oyster larva? before I could feel satisfied that the 

 latter were in reality larvae of the oyster. Of the common 

 bivalve mollusks only Ostrea and Anomia live fixed to 

 objects of support, so that the matter has some appear- 

 ance of simplicity in the fact that all free-living forms 

 may be eliminated. But careful examination of eel-grass, 

 rock-weed and other marine plants, of shells, stones, 

 timbers and other objects revealed no young spat, and I 

 was forced to wonder where the oyster secreted itself at 

 this stage of its life. I examined sand with the micro- 

 scope to find if, like many bivalves, the young oyster 

 might burrow for a time, but with no better result. 

 Bundles of brush were tied to submerged rocks, or 

 weighted with stones and sunk at various places. These 

 were examined at intervals but without success. Each 

 failure suggested some new possibility that required 

 examination and occasioned delay. Time was flying, it 

 was getting late in the season, and each day brought no 

 further progress. What stupendous obstacles present 

 themselves to the investigator and how simple after one 

 has once mastered them! 



time by Professor Wright, was particularly opportune, 

 and I owe to it much by way of information and suggest- 



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