764 KEPOET OF COMMISSIONER OF FISH AND FISHERIES. [2] 



ilium* The filaments are capable of straightening out and contorting 

 themselves into a great variety of forms. The usual shape of these or- 

 ganisms is that of an apparently spiral thread of extreme tenuity, which 

 exhibits lively movements of progression in right lines, like the Oseil- 

 latorice, Diatoms, and lower Algce in general. In consequence of the 

 power which the filaments have of bending themselves, they may also 

 exhibit vermicular movements. This organism is sometimes found in 

 prodigious numbers in the vicinity of the crystalline style. Sewage is 

 not the source of it, because this Spirillum [Trypanosoma] is found 

 equally abundant in the stomachs of oysters from muddy or from clean 

 bottoms, from deep or shallow water, and far from any possible source 

 of sewage contamination. I also found the tests of a Difflugian in an- 

 other instance, with the sarcode digested out ; the species api)ears to 

 be Bifflugia acuminata Shr.t The cephalula stage of development of 

 some worm, species not identified, a mass of vivid green algous cells, 

 stellate hairs from the leaves of a neighboring exogenous tree, fila- 

 mentous algse and desmids, completes the list of organisms and organic 

 remains encountered in the gastric contents of the oyster when examined 

 microscopically. Many more might doubtless have been found, had one 

 taken the trouble to spend time in the search. 



To-day, at 2.50 p. m., I fertilized a lot of oyster ova ; examined about 

 fifty adults in full spawning condition ; but in consequence of the fact 

 that the water-supply fixtures were not yet in working order, I gave up 

 experimenting for the present. 



The interim from the 3d to the 10th of July was employed in getting 

 our equipment into shape for the work. 



July 10. — Impregnated a lot of eggs of the oyster at 3 p. m. to-day; 

 not a very good lot. Had some difficulty in finding a ripe male; but 

 the second lot fertilized at 3.30 p. m. came out much better and began 

 to segment normally within an hour after the time of impregnation. 



July 11. — Best lot of yesterday at 3.30 p. m. had the velum distinctly 

 developed to-day, with the shell-gland formed or forming. Tempera- 



[* I leave my original descriptiou of this organism as I wrote it in 1882. M. A. Cer- 

 tes, in his ^^ Note sur les parasites et les commensanx de Vhuitre," Bull- de la See. Zoologique 

 de France, 1882, describes and figures what is evidently the same organism under the 

 name of Trypanosoma Balbianii, and shows that, instead of being s})iral as I have de- 

 scribed, it is really provided with an extremely thin spiral frill wound around the 

 very slender fusiform body, the frill being the locomotive apparatus of the organism. 

 It measures about ^iuth of an inch in length. From M. Certes' description, which I 

 have since verified, it is evident that I am in error in regarding it as a Spirillum, and 

 that it is, consequently, probably not to be considered as belonging to the group of 

 Schizomycetes at all. (January 3, 1884.)] 



[tThis may have been the test of a species of Tintinnvs, a peritrichoua infnsorian, 

 some of the species of which build a chitinous case covered with grains of sand very 

 like the tests of Diffiugia acuminata. For further facts regarding Tintiitnus as food for 

 the oyster, see my paper entitled " Rearing oysters from artificially fertilized eggs, to- 

 gether with notes on pond culture." Bull. U. S. Fish Commission, III, 1883, p. 293. 

 (January 4, 1884.)] 



