THK ATTACHMENT OF OYSTER LARV.-E. 141) 



I-'ig. 4 >how- in a circle 6 mm. in diameter a group of 40 o\ 

 larva- ju>t attached to an experimental shell. Unfortunately I 

 have never witnessed the behavior of two oyster larvae coming 

 intu contact with each other while circling about over a surface, 

 Inn an examination of shells taken at times of maximum settle- 

 ment indicates that the movements of the larva? prior to final 

 fixation not only aid them in finding a spot suitable for attach- 

 ment, Inn that this behavior also tends to keep the larvae sep- 

 arated from one another. The proximity of a neighboring larva 

 could presumably be recognized only through touch, hence it is 

 conceivable that here and there individuals failing to come in 

 contact while circling about might attach close to one another, 

 .1- ci urred in six instances in Fig. 4. Kxamination of the nn>-t 



FIG. 4. Newly attached oyster larvae on the - !i< -11. Within 



tliis circle, 6 mm. in diameter, are 40 larva?. Mai;iiiti<-.| about i 5 



heavily set shells in our collection -lx>\\- .in .| v>o newly at- 

 tached larva 1 only 57, or 11.4 per cent., \\liicli are within .5 mm. 

 of another larva. This distance is taken since ii repiv-ents the 

 approximate radius of the circles described l>v the larva- when 

 observed. Studies of the behavior of other bival\e larva? 



