STOMAPODA. 295 



right claw, which is the largest. It is common in European seas. In another 

 (Antaeus, Fab.) we find the Astacus marinus or Common Lobster. The fresh 

 water species are known by the name of Craw-fish. Among these also we 

 find the Shrimp (Crangon), and the Prawns (Paltemon). 



ORDER II. 

 STOMAPODA. 



THE branchiae of the Stomapoda are exposed and attached to the five pairs 

 of sub-abdominal appendages, exhibited to us by that part of 

 the body, called tail, in the Decapoda, and which here, as in 

 most of the Macroura, are fitted for swimming, or are fin-feet. 

 Their shell is divided into two portions, the anterior of which 

 supports the eyes and intermediate antennas, or composes the 

 head without giving origin to the foot-jaws. These organs, as 

 well as the four anterior feet, are frequently approximated to 

 ihe mouth on two lines that converge inferiorly, and hence the denomination 

 of Stomapoda affixed to this order. 



The teguments of the Stomapoda are thin, and in several nearly membranous 

 or transparent. The shell is sometimes formed of two shields, of which the 

 anterior corresponds to the head and the posterior to the thorax, and some- 

 times of a single piece, which however is free behind, usually exposing the 

 thoracic segments bearing the three last pairs of feet, and having t an articu- 

 lation before that serves as a base to the eyes and intermediate antennae ; these 

 latter organs are always extended and terminated by two or three threads. 

 The eyes are always approximated. The formation of the mouth is essentially 

 the same as in the Decapoda ; but the palpi of the mandibles, instead of being 

 laid on them, are always vertical. The foot-jaws are deprived of the flagelli- 

 form appendage presented to us by the same parts in the Decapoda. They 

 have the form of claws or of sma 1 ! feet, and, at least in several the Squillae, 

 their external base as well as that of the two anterior feet, properly so called, 

 exhibits a vesicular body. 



The Stomapoda are all marine Crustacea. Their favourite habitat is in the 

 intertropical latitudes, and they are not found beyond the temperate zones. Of 

 their habits we are totally ignorant; that those which are furnished with claws 

 use them in seizing their prey, in the manner of those Orthoptera called 

 Mantes, we cannot doubt. Hence their vulgar appellation of Sen-Mantis: they 

 are the Crangones and Crangines of the Greeks. According to Risso they prefer 

 sandy bottoms in deep water. Other Stomapoda, those of our second family, 

 being less favoured with natatory appendages, and having a much flatter and 

 more superficially extended body, are generally found on the surface of the 

 water, where they move very slowly. We will divide the Stomapoda into two 

 families. 



