LtEMOUIPOUA. 42y 



the onliT Isnpnda), namely, the Ci'evettiiies and tlie ITyperines, the former diviih.'d into the sallatinial 

 and ambulatory sjiecies. Some new genera were added, especially in the singular family of llie llyiierini s. 

 Pleryij'icera, Latr., and some other genera, he considers not snffieiently s-tudied, ami consi.i|uently ol 

 doubtful character and situation. Jp^ciides, /oni?, Jnceus, a)id Pt'anha, lie al>o reyard^ as l^o|lO(!oui. 

 Various additional genera have also been establislied by M. Guerin de Mencvillc, in tlie MojjnxUi ile 

 Zooiogie, especially amongst the ITyperines, and which are accompanied by figures and generic details. 

 Dr. Templeton has described some curious minute species from Mauritius, in the Transac/ious of f/ie 

 Entoinolo(jLcal Society. Still more I'ecently I have received from j\I. Kroyer, tlie Danish naturalist, a 

 memoir upon the Amplu[ioda of Crectdand, published in the last part of tlie Cu/jcnhnt/eit Tran-^actiouf!. 

 Ratlike has described many new species, and some new genera from the Caspian Sea, in the last voUune 

 of the Pefersbiirf/ Memoir!;, and Professor Owen has descri1)ed some interesting species In'ought home in 

 one of tlie late Polar exjiedilions. One of the most remarkable of the subgenera established, is that of 

 Orio of A. Cocco, described in the Gwrnali di Scicfize, Sfc, per la Sicilio., for November ] 83.3, which has 

 been overlooked by Crnstaceologists, and in which the maxillary palpi are exceedingly slender, as long 

 as the body, and 4-jointed.] 



THE FOURTH ORDER OF CRUSTACEA, 



LOSMODIPODA,— 



Comprises the only ilalacostraca with sessile eyes which have not distinct hranehia? attached 

 at the extremity of the body, which are nearly destitute of a tail, the hmd pair of legs being 

 attached cither at the extremity of the body or to a segment, followed by one (n- two very 

 small joints. They are also the only species m which the twci fore-legs, which correspond 

 with the second foot-jaws, form part of the bead. 



All the species have four setaceous antenn;e, implanted on a peduncle of three joints ; 

 mandibles destitute of palpi ; a vesicular body at the base of at least four of the pan-s of legs, 

 commencing with the second or third pair, inclvuling those of the hi'ad. The body, generally 

 filiform or linear, is composed (including the head) of eight or nme segments, with several 

 small appendages in the form of tubereles at its posterior and mferi(U- extremity. The legs 

 are terminated by a strong honk; the four anterior, of wdiieh the second pair is the largest, are 

 always terminated by a monodactyle claw. In some, the four following are more slender, 

 with fewer articulations, without a terminal hook, or are nidimental and in no manner fitted 

 for the ordinary uses. 



The females carry their eggs beneath the second and third segments of the boiH', in a pouch 

 formed of scales closely applied against each other. 



All these Crustacea are marine. 51. Savigny considers them as apjproachiug the Pvcno- 

 gonidcs, and as fcnaning, together with them, the passage between the Crustacea and 

 Avachnida. In the first edition of this work, they formed part of the Isopodous order, namely, 

 the section Cystilnanchitc. 



Thcv may be considered as forming a single genus, for which, on account of its priority, the name of 



Cyamus (Latr.) — 

 should be retained. 



Some of these (forming a first section named Filiformia, Latr.) have the body long and very slender 

 or linear, with the segments longitudin.al ; the legs also long and very slender, and the terminal fila- 

 ment of the antenna; composed of minute joints. 



Thcv are found amongst marine ]daiits, creeping along in tlie same way as the Geometer or Looper- 

 catcrpillars, bending themselves often back with great rapidity, and applying their antenna; to various 

 parts of the body. In swiinniing they bend the two ends of the body downwards. 



