58 FISH—CULTURAL ASSOCIATION. 
T. B. Ferguson, for the year 1881, which has been favorably re- 
ceived. Additional papers have been contributed for the same 
report for 1882, and to the Bulletin of the U. S. Fish Commis- 
sioner, bearing mainly upon the anatomy, finer structure and 
development of the animal. An imperfect list of the published 
works on the subject has also been compiled by the writer; a 
more complete catalogue, embracing its literature in all lan- 
guages, will shortly be published by the Dutch government. 
What has already been put upon record it will not be worth 
while to discuss, and we will therefore recapitulate only when 
necessary, adding new facts not yet recorded. To our knowledge 
of the early development of the animal we have added nothing, 
and thé account as given by Brooks for the American, and Sa- 
lensky, Gerbe, Fischer and Davaine for the European species, 
with little qualification, remain the same. The detachment of 
the ring or crown of vibratory filaments or cilia from the em- 
bryo oyster, as asserted by Davaine, has not been confirmed by 
any other observer. Hatschek has lately contributed some val- 
uable researches in regard to the development of young bivalves, 
working, however, upon the young ship-worm. His studies 
have no direct bearing upon the development of the oyster, but 
they nevertheless throw considerable Hight upon the mode of 
formation of the gills, upper gill-chambers, liver, muscle, foot 
and nervous system of the great group to which they both be- 
long. Hatschek’s observations show that the conversion of a 
part of the velum or ciliary crown above and below the mouth 
into palps and gills, as held by Lankester, does probably not 
take place. The occurrence of ciliary bands running from the 
edge of the mantle on its inner side to the mouth, as observed 
by the writer in “ spat” one-eighth of an inch in diametcr, was 
supposed at first to confirm Lankester’s view, but Hatschek’s 
researches have made such an opinion untenable. The physio- 
logical function of these bands was, however, clear; by the 
vibration of the filaments composing them they establish cur- 
rents which hurl the microscopic food of the surrounding water 
down into the throat of the young “spat,” thus serving, in 
fact, the same purpose as the velum adjoining the mouth ot the 
8 hayes? 
