Tulian. — Shrimp Production in Louisiana 117 



resembling the former, with which it is sometimes associated. 

 The antennas of the Brazilian prawn are comparatively short, 

 being less than twice the length of the animal, while in Penceus 

 setiferus they are over twice the entire length. The rostrum in 

 both species usually has nine spines on the upper edge, but in 

 Pencsus braziliensis it is bordered on either side by a groove where 

 it keels the cephalothorax. This groove is absent in Pencsus 

 setiferus. Penceus braziliensis is also of a more greenish color, 

 mimicking the greenish vegetation with which it is usually 

 associated, while Pencsus setiferus has a clearer "complexion," 

 showing a preference for open waters which are bare of living 

 vegetation. 



Penceus braziliensis is not recognized by the fishermen as a 

 distinct kind of shrimp and whatever small per cent is caught by 

 them is marketed with the ordinary lake shrimp. They seem to 

 make their appearance earlier, however, and in the month of 

 June when the young lake shrimp have not appeared as yet on 

 inside waters in appreciable numbers, catches of this species 

 unmixed with any of the others are quite common. They are 

 never as abundant as either the sea-bob or the lake shrimp, and 

 consequently are almost negligible as a commercial proposition. 

 Adult specimens of Penceus braziliensis have never been observed 

 in Louisiana and nothing is known of its breeding habits. 



The adults of Penceus setiferus average between six and eight 

 inches, and the cephalo-thorax especially in the female is very 

 large compared to that of immature specimens. In the ripe 

 female the ovaries are very large and fill a considerable portion 

 of the cephalo-thorax, extending down the back to the very tip 

 of the abdomen. 



That the Conservationists of Louisiana appreciate the value 

 of the salt water shrimp resources of the State is evinced by the 

 fact that as far back as 1906 a study of their life history and habits 

 was commenced at the State Gulf Biologic Station, located at 

 Cameron, Louisiana, and continued until the station was aban- 

 doned several years later. 



A considerable amount of valuable information along the lines 

 mentioned was obtained by H. M. Spaulding, M. S., Zoologist 

 in charge of Experimental Work, Wm. H. Gates, and others. 

 In December, 1912, the U. S. Commissioner of Fisheries wrote 



