414 M. E. Hesse on the Pranizae and Ancei. 



branchiae ; they also attach themselves to the body, and are fre- 

 quently found upon its surface, having probably escaped from 

 the mouth or gills when alarmed by the capture of the fish. It 

 is chiefly in the months of July, August, September, and October 

 that Pranizce are met with upon fishes. 



On the shore, the Praniza and Ancei are usually found under 

 sea-weeds, especially the Solenice which grow upon the walls of 

 harbours; they also hide themselves in the interstices of the 

 masonry, or under stones slightly covered with mud. In the 

 P/'flniza- state, they do not seem to fear either heat or light, or 

 to suffer by the absence of water ; in this state, also, they are 

 extremely active, swimming and running with great rapidity. 

 Natation is effected by means of the abdominal feet, the animal 

 extending itself horizontally, and holding its legs extended in 

 the attitude of walking : it swims in circles, in the manner of 

 the Caligi when seeking a fish to which to attach themselves. 



In the perfect state, the Ancei are far less active, swimming 

 and walking very little and with difficulty, and hiding themselves 

 from the light; their habits are evidently sedentary, and in 

 striking contrast to their previous mode of life. They then lie 

 constantly on the shore, in little burrows or galleries. Their 

 bodies being thus protected, their large mandibles may serve to 

 defend them against all aggressions from without ; and that they 

 constitute powerful cutting organs is evidenced by the fact, ob- 

 served by the author, that when several male Ancei are kept to- 

 gether in a vessel, the limbs of some of them will be amputated 

 by a clean cut. They probably serve also for the purpose of 

 seizing prey, although the author attributes to the ciUated 

 laminae of the mouth a certain part in procuring nourishment 

 consisting of Infusoria and minute Mollusca and Crustacea. 



On the Food of the Ancei. 



As to the nature of the food of these animals, however, 

 M. Hesse does not appear to have arrived at any positive cer- 

 tainty. In the Praniza-state they live on the shore, under stones 

 or seaweeds, about which the author found the debris of animal 

 and vegetable substances, small Crustacea, Mollusca, &c. By 

 furnishing his hving specimens with similar articles, the author 

 was unable to bring his Praniza to maturity; and all those which 

 he obtained from the ova died in about six weeks after their 

 exclusion. Nevertheless some of those which he collected in an 

 early form on the shore arrived at their full size in his aquaria ; 

 and their not undergoing their final metamorphosis is probably 

 due to their being females, which could not be transformed until 

 after they had received the influence of the male. All those 

 collected froih fishes became converted into Ancei in a few days 



