94 OUR CARCINOLOGICAL FRIENDS. 



of a light-green color, or nearly colorless, and often 

 quite translucent. In this country they are not so 

 highly esteemed as an article of food as they are 

 in either England or France, where the prawn- 

 fishery constitutes an important branch of industry. 

 Our common shrimp {Crangon vulgaris, PI. 7, Fig. 

 8), which can be distinguished from the prawn 

 (Palsemon, PI. 7, Fig. 9) by the terminal joints of 

 the two anterior pairs of legs being undivided, and 

 by the filiform structure of the succeeding legs, does 

 not appear to diifer from the ordinary European 

 species. It is abundant in the waters of the sandy 

 flats, where by reason of its har- 

 monizing coloring it escapes ready 

 detection. Both shrimps and 

 prawns are frequently infested 

 with a loathsome parasite, which 

 attaches itself as a round black 

 mass on one side of the neck of 

 the victim. This parasite is in 

 itself a crustacean, known to nat- 

 uralists as Bopyrus. 



A so-called shrimp, not to be 



Pandalus. - , - . , . 



confounded with either or the pre- 

 ceding, is the Mysis stmolepis (PI. 7, Fig. 1), which 

 appears more abundantly about our coasts during 

 the winter months. It may be distinguished from 

 the true shrimps by its cloven or double feet, and by 

 the external position of the gills. From the circum- 

 stance of its carrying its eggs in a pouch underneath 

 the thorax it has received the familiar name of 

 ' opossum shrimp,' by which it is generally known. 



