69 



of the appearance of the Chesapeake Bay oyster when 

 about two years old. The animals when divested of 

 their shells were larger than those of the same species 

 from other localities, and were all in good condition, the 

 ova and spermatozoa being ripe, in many cases oozing 

 from the oviducts, and in all cases in admirable condi- 

 tion for artificial fertilization, the eggs being well de- 

 fined, and with but little granular matter among them, 

 while the spermatozoa were exceedingly active. 



I had intended to examine carefully the ovaries, gills 

 and mantles of all the oysters at my disposal with the 

 intention of detecting the existence, should there be any 

 embryos within the shell, but the pressure of other du- 

 ties and the disadvantages under which I labored left me 

 but little time and few opportunities to devote to the 

 matter, and consequently I am unable to state positively 

 that in some among the limited number in my possession, 

 the embroys were not fostered within the shell of the 

 parent. I was able to examine between twenty and 

 thirty oysters only ; these at least contained no embryos, 

 though some of them were expelling the contents of the 

 generative organs, as I found on the gills of two, ova 

 unimpregnated, and on the gills of another, spermatozoa.* 



In making the experiment I followed carefully the 

 method of Dr. W. K. Brooks, as described by him in 

 his paper on the development of the Americon oyster, 

 (Report of the Commissioners of Fisheries of Maryland, 

 1880,) and I am compelled to refer to his figures, given in 

 that report, from the want of suitable instruments and 

 conveniences for making those of my own. As I care 

 fully followed the development of the eggs through each 

 stage, comparing those under the microscope with the 

 figures at frequent intervals, as the successive stages of 

 development are well marked, and as I have witnessed 

 many of them in company with Dr. Brooks, and have 

 likewise observed them while working index)endently 

 during the summer of 1879, I think my observations may 



