440 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



96.-KEPOBT OX THE A^NORMAI, APPEARANCE OF SHAD EGGS 

 FROM A FISH KEPT IN COXFIMETlEJiT AT HAVRE »E GRACE, 

 NAltVLAND. 



By JOHN A. RYDER. 



[From a letter to Prof. S. F. Baird.] 



Mr. F. N. Clark yesterday sent me a shad with roe which was pecu- 

 liarly affected; it was one of a lot which had been kept in confinement 

 in the "pound" at Havre de Grace. I find the ovarian eggs in large 

 part mature and ready to be emitted, but they present some singular 

 and unusual abnormal appearances. Of these the most striking are 

 the following: 



The egg-membrane seems to be slightly fuller than when in the con- 

 dition usually met with, and the germinal matter is frequently elotted 

 and dead, with a peculiar tendency towards fluidity not to be observed 

 in normal eggs. It seems to me as if the fish in holding the eggs for 

 an abnormally long time had produced the effects noted. My own idea 

 is that it is likely that confining an anadromous fish like the shad we 

 will have just such a result. We know that confinement produces ster- 

 ility in many animals, and it may be that this is one of the effects of 

 such confinement in this particular instance. Nature will oftentimes 

 revenge herself, so to speak, if too immoderately interfered with. The 

 ripening process seems to have been normal in the ovary, but whether 

 the influence of confinement had something to do with interfering with 

 a perfect maturation of the eggs I am still unable to decide, as my 

 investigations are not yet completed. 1 have therefore saved some 

 material for this purpose, in the hope that I may get some more data 

 upon this point. The vitellus in the eggs examined by me was much 

 altered from the normal appearance which it ought to present. If 

 looked, indeed, as if the germinal and deutoplasmic or yelk material 

 had suffered admixture. Impregnation of such ova would evidently be 

 out of the question. 



Washington, D. C, May 31, 1883. 



!ir.-t'ATCH OE SPAWMXfi SHAD IIV THE POTOMAC ABOVE GEORGE- 

 TOWN. 



By J. T. EENNURT. 



There are being taken daily at this place, by one fisherman on the 

 Virginia side and two on the Maryland side of the Potomac River, from 

 30 to 40 enormous-bellied shad. The spawn Hows freely from them as 

 they come out of the water. A quart could often be taken in the spot 

 where the fish lie on the rocks. 



Chain Bridge, Va., June 20, 1883. 



