REPORT OF COMMISSIONER OF FISH AND FISHERIES. 99 



Dr. Dean, who had carried on successful experiments during the 

 spring - respecting the artificial hatching of the sea sturgeon (Acipenser 

 sturio) on the Delaware River, continued at Woods Hole the detailed 

 study of the material collected and preserved at that time. 



The subjects pursued by the independent investigators were mainly 

 as follows: Dr. Andrews, the anatomy of certain annelids; Dr. Patten, 

 the structure, physiology, and development of the horseshoe-crab; Dr. 

 Schiedt, the anatomy and physiology of the oyster, an interesting" con- 

 clusion based upon some of his experiments being that the presence of 

 great quantities of minute algae in the water is unfavorable to the life 

 of oysters, the gills and palpi becoming so clogged as to interfere with 

 the freedom of ciliary action, causing the animals practically to starve 

 because of a superabundance of food; Professor Kellicott, the marine 

 rotiiera and infusoria; Dr. Ryder, the habits and life history of a fresh- 

 water polyp and the bathymetric relations and distribution of the 

 foraminifera; Miss Carter, the micro-organisms affecting the alimen- 

 tary canal of the mackerel and other fishes, a new field of study of 

 probably great economic importance as well as scientific interest; Miss 

 Hyde, the physiology and mechanism of the respiratory movements of 

 the horseshoe-crab, and the ontogeny of several forms of jelly-fishes; 

 Miss Cooke, the physical factors in the modification of the form and 

 life phenomena of the lower animals; Mr. Graham, the development of 

 the sea bass. 



The season's work will result in the preparation for publication of 

 at least 23 papers, all of scientific value and several of great economic 

 importance. 



Mr. Yinal N. Edwards, who has been attached to the station at 

 Woods Hole since 1871, has continued his regular natural-history 

 observations throughout the year, keeping a daily record respecting 

 the presence, movements, etc., of the different fishes occurring in the 

 region. In this connection the catches made by the local fishermen are 

 closely examined and seines and other nets are constantly employed by 

 him for this special purpose. Mr. Edwards has also conducted impor- 

 tant investigations relative to the mackerel, menhaden, and lobster, as 

 described elsewhere. 



The season of 18!>4: was opened on June 4 by the arrival of Mr. J. 

 Percy Moore, who was again designated to take charge of the labora- 

 tory, with instructions to begin upon a special study of the embryology 

 and spawning habits of the common mackerel. Investigations relative 

 to the natural history of the mackerel in connection with the fishery 

 for that species off the southern coast of New England by Dr. Wol- 

 haupter and Mr. Edwards were already in progress at this place, as 

 elsewhere explained. Before the end of June the following additional 

 investigators had also arrived: Mr. W. E. Castle, of Harvard Pniver- 

 sity; Mr. Ulric Dahlgren, of Princeton College; and Mr. X. P. Harring- 

 ton, of Williams College. 



