STOMAPODA. 425 



These minute and delicate Crustacea are peculiar to the Atlantic Ocean and the Indian Seas. The fingers of the 

 larg-e claw-leg-s are not toothed. The second joint of the ocular peduncles is much larg-er than the basal joint, and 

 in the form of a reversed cone. The eyes themselves are large, and nearly globular. The appendages of the 

 swimming or fin-feet resemble those of the Sqaillte. 



Erichthus, Latr. {Smerdis, Leach), has the basal joint of the ocular peduncles short, and the carapax dilated at 

 the sides. Type, E. vitreug, Latr. 



Alhiia, Leach, has the basal joint of the ocular peduncles much longer, the body much narrower, with the sides 

 of the carapax not dilated. Each of its angles forms a spine, of which the two posterior are the most acute. Type, 

 A. hyalina, Latr. 



[Squillericthus, Edwards, has the claws of the great feet armed with spines.] 



THE SECOND FAMILY OF STOMAPODA,— 

 BiPELTATA, Latr., — 

 [Comprises the Glass-Crabs, which] have the carapax divided into two shields, the anterior of which 

 is very large, more or less oval, composing the head, and the second, corresponding with the thorax, is 

 transverse and angulated in its outline, and hears the foot-jaws and the ordinary feet. 

 Those feet, with the exception of the posterior pair, as well as the last pair of foot- 

 jaws, are slender, filiform, and for the most part very long, and accompanied by a 

 \ '~~F^ / I'l^^i'^^' ciliated [short and slender] appendage. The fom" other [anterior] foot-jaws 

 "^"Ov liH ill />v^ """^ ^^^y minute and conical. The base of the lateral antennas is not furnished with 

 a scale, and the intermediate ones are terminated by two filaments. The ocular pe- 

 ^-^'^^W^^^^- duncles are very long. The body is very flat, membranous, and transparent, with the 

 ijg. lo.-Phyiiosonifi abdomcH small, and without spines to the posterior swimmeret. In respect to their 

 ciavicornib. nervous system, they appear to be intermediate between the preceding and following 



Crustacea. 



Tills family comprises only the single genus PhyUosoma, Leach, of vvhich all the species are inhabitants of the 

 Atlantic and Eastern Oceans. [IVL Gudrin has published a monograph of this genus, with figures of all the species, 

 in his Magashi de Zoologie.l 



[XL Edwards has recently added another genus, Amphion, differing from PhyUosoma in its narrower body, and 

 in the carapax extending behind over the whole body, thus rendering Latreille's name, Bipeltata, inapplicable.] 



Those Malacostraca which have the eyes sessile and immoveable, form the second 

 general subdivision, [and have been collectively named Edriopthalma by Leach] . 



The [Branchiopodous genus] Branchipus comprises the only Crustacea which remain 

 to be noticed, having the eyes placed on long footstalks ; but in them the peduncles are 

 neither articulated nor lodged in cavities expressly for their reception, and they are 

 not only destitute of a carapax, but differ in many other natural characters [from the 

 Podopthalmous Malacostraca] . 



All the Malacostraca of the present [sub] division are equally destitute of a carapax. 

 The body, following the head, is composed of a series of articulations, of which each of 

 the seven anterior ones is generally provided with a pair of feet, and of which the 

 following and terminal segments (not exceeding seven in number) form a kind of tail, 

 terminated by a swimmeret, or appendages in the shape of styles. The head is 

 furnished with four antennre, of which the two intermediate ones are suj^erior ; two 

 eyes, and a mouth composed of two mandibles, a tongue, two pair of maxilla;, and a 

 sort of lip formed by the two foot-jaws, which correspond with the fourth [or inner] 

 pair in the Decapoda ; as in the Stomapoda there is no flagrum. The four outer foot- 

 jaws are transformed into feet, sometimes simple, sometimes terminated in a claw, 

 but almost always with a single finger. According to MM. Audouinand Edwards, the 

 two ganglionated nervous cords are perfectly symmetrical and distinct throughout their 

 entue length, and from the observations of Cuvier the Onisci only differ in tliose cords 

 not presenting the uniformity in all the segments of the body, and that there are fewer 



