166 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [460] 



Antliosouia crassurn, on mackerel-shark. 



Lerna3a branchialis, oil cod-fish. 



Penella plumosa, on Diodon pilosus and Ehombus, sp. 



Anchorella uncinata, on cod-fish. 



Lernaeonema radiatum, on menhaden, (458.) 



Lerna3onenia 7 sp., on a species of Carangus. 



Corouula diadema, on whales. 



Leeches. 



Branchiobdella Eavenelii, on sting-rays ; August, September, (458.) 

 Cystobranchus vividus, on minnows ; October to December 18, (458.) 

 Ichthyobdella Eunduli, on minnows ; with last, (458.) 

 Ichthyobdella, sp., dredged off New London, April. 

 Pontobdella rapax, on flounders, (458.) 

 Malacobdella obesa, in long clams, (458.) 

 M. merceuaria, in round clams, (458.) 

 Myzobdella lugubris, on the edible crab, (458.) 

 Bdelloura Candida, on gills of Limulus. 



MOLLUSCA. 



Gastropods. 



Stylifer Stimpsonii, on the green sea-urchin. 

 Eulima oleacea, on Thyone Briareus, (418.) 



III. FAUNA OP THE ESTUARIES, HARBORS, PONDS, AND MARSHES. 



The region about Vineyard Sound and Buzzard's Bay, like that of the 

 entire southern coast of New England and the coast farther south, is 

 characterized by large numbers of ponds, lagoons, and estuaries, having 

 a more or less interrupted communication with the sea. These are 

 usually quite shallow, though often of great extent. The bottom is 

 generally muddy, with occasional patches of sand, but at the surface 

 usually consists largely of decaying vegetable and animal debris mixed 

 with mud. 



The " eel-grass" (Zostera marina) grows in the shallower waters in 

 great quantities, sometimes in small scattered patches, at other times 

 covering large areas. Some of these ponds and estuaries receive con- 

 siderable, though variable, quantities of fresh water from streams flow- 

 ing into them, while others receive but little, except the surface drain- 

 age of the land immediately around them ; but in most of them the 

 fresh water is in sufficient quantities to give a " brackish" character to 

 the waters. Owing to the narrow and often shallow channels by which 

 the ponds communicate with the open waters, the tide is usually irreg- 

 ular, and its rise and fall often much less than outside, so that the wa- 

 ters have little tidal motion. The shallowness of the water and the abuu- 



