76G KEPOET OF COMMISSIONER OF FISH AND FISHERIES. [12] 



report, for 1875 aud 1876, on the winter habits of the fishes of the Del- 

 aware. Mobius has found pieces of Algae, besides Shells, Snails, Crabs, 

 and fishes in the stomach of the cod. The writer has found the stomach 

 of the sheep's-head filled with the remains of the shells of mussels and 

 large quantities of the slender branches of the common bright red sponge, 

 Microciona jiroliferum, bitten off in short fragments by the incisor-like 

 teeth of the fish, and with the red sponge sarcode partly digested out of 

 its skeleton. It is presumed that the sponge feeds upon protozoan life, 

 and on account of its peculiar dentary armature the sheep's-head is 

 singularly well fitted to pasture upon sponges and thus indirectly ap- 

 propriate Protozoa as nourishment. The same remark applies to the 

 molluscan food of this fish. 



In young shad from Capehart's fishery, Albemarle Sound, said to have 

 been three weeks old, I found the remains of a number of adult Tipiili- 

 dee, or crane-flies, in the intestine. This reminds me that in examining 

 the larvge of crane-flies some years ago I was struck with the fine comb- 

 like fringes which garnish the edges of their wide oral appendages, and 

 which are so extended in life when the lar%'a is in motion as to consti- 

 tute a sort of basket which opens downwards and for-vyards apparently 

 to strain out of the water the small organisms which constitute its food. 

 Here again we have young shad feeding upon an arthropod which has 

 passed its larval existence feeding in great part upon Protozoa. West- 

 wood (Introd., ii, 511) I find makes a similar observation in regard to 

 the larvae of the gnat or mosquito family. He says : "The head is dis- 

 tinct, rounded, and furnished with two inarticulated antennae, aud sev- 

 eral ciliated appendages, which serve them for obtaining nourishment 

 from their food." 



The fixed Tunicates are probably as dependent upon the microscopic 

 life swimming .about them in the water as the Lamellibranchs. The 

 Barnacles in like manner, immovably fixed during their adult existence, 

 kick their minute food into their mouths with their filiform legs, as 

 remarked by Huxley. In Fedicellina americana, abundant in Saint 

 Jerome's Creek, I have observed that there are rows of vibratory cilia 

 continuous with those of the tentacles around the edge of the lopho- 

 phore, which appear to lie in grooves, which blend on either side of the 

 excentrically placed mouth. In this manner the microscopic food of 

 this curious Bryozoan is conveyed in ciliated grooves to the mouth 

 from all points of the oral disk. With these we may close our survey 

 of the modes in which the protozoan grade of life is appropriated the 

 smaller Arthropods, Pteropods, Polyzoa, Annelids, and Tunicates, but 

 we must remember that upon these again the larger forms subsist, 

 which are either food for each other or for man. As we pass in succes- 

 sion the larger forms, we may note the Lamellibranchiates, with this 

 garniture of vibratory cilia covering the gills and palps, and which 

 carry the i)articles of food and sediment suspended in the water used 

 in resi)iration to the mouth to be swallowed. The Clupeoids and Getio- 



