8TOMAPODA, 



STOMAPODA. 



forming a wide belt within it* margin, the youngest swimming nearest 

 to the thorp, the oldest farther out and in deeper water. They appear, 

 be adds, to be mostly females, the male* being few in proportion, and 

 they iwim in & horizontal position, contributing toward* the food of 

 various young fih, from which they frequently escape by ipringiug 

 up out of the water. 



2nd Tribe. Lueiferians. 



M. Milne-Edwardi observes that the genus Licifer, established by 

 Mr. Thompson, is one of the most singular known. One of the most 

 remarkable traits of this crustacean is the excessive length of the 

 anterior portion of the head ; the extreme brevity of the part of the 

 body occupied by the mouth, and constituting the thorax ; and the 

 great development of the abdomen. 



The general form of the body is nearly linear. Eyes and antenna) 

 curried at the extremity of a long, slender, and cylindrical prolonga- 

 tion, which is much longer than all the rest of the cephalo-thoracio 

 portion of the body, and seems to be formed principally by the anten- 

 nary ring. A small carapace covers the whole of the posterior portion 

 of the ccphalo-thoraz, and presents nearly the same form as in Myn*. 

 The first pair of antenna) ore slender, Jshort, and terminated by a multi- 



rticulate rudimentary stemlet ; the second pair are inserted below, 



lose to the preceding, and are equally slender : near their base is 

 seen a small lamellar appendage, but their mode of termination is 



nknown. Month projecting, and situated behind the base of the 



irolongation which entries the eyes, &c. 



L. Typia. This species differs from the only other Krynaudii (which 

 was found in the Indian Ocean by M. Reynaud) in the form of tho 

 median piece of the caudal fin, which H lamellar, and without any 



otch below, in the more considerable length of the middle blade.-, 

 and in the apparent absence of a separation between the carapace oud 



culift runs prolongation. 



J/>it r/fflru, magnified. (Tnompton.) 



Cyn/iia, Thompson. Body slender, and of the same form as in 

 jl/ytu ; but the carapace of Cynthia is smaller, and terminates ante- 

 riorly by a small rostral prolongation ; behind it a certain number of 

 thoracic rings are exposed. Eyes stout and short, of moderate length. 

 First pair of antenna! excavated at their base to make room for the 

 eye* ; their peduncle is stout, and they have two terminal filaments. 

 The second pair of antenna are inserted below the preceding, as in 

 ifyta, but they are much smaller; the lamellar appendage which 

 covers their base is shorter than the peduncle of the upper antenna?. 

 Conformation of the buccal apparatus nearly the same as in Alyiu ; 

 palpiform stem of the mandibles very large ; second pair of jaws 

 lamellar, and divided on the internal side into many lobes. 



C. Tkamptanii, a native of the Atlantic Ocean, between Madeira and 

 the Antilles. (Milne-Edw*rd>.) 



Tkytttnopoda (Milne-Edwards). External form resembling that of 

 Myrit. Body presenting the same divisions as in the Macrourous 

 Decapods. Carapace, which covers the head, hiding also the whole of 

 the thorax. Abdomen, whose length much exceeds that of tho 

 C'-phalo-tborax, extended backwards, and composed of seven segments, 

 the three median of which present on their posterior and superior 

 borders a small spine, directed backwards. Carapace terminated 

 anteriorly by a small pointed rostrum, which does not reach to the 

 extremity of the eyes, whose peduncles are stout and short. Antenna; 

 four in number, inserted on two lines, and nearly equal in length ; 

 the upper with a peduncle recurved at it* base, to receive the eye*, 

 and composed of three cylindroid joints ; they are terminated by two 

 rather long filiform stems. Base of the lower antennto covered by a 

 long lamellar scale, the extremity and internal border of which are 

 ciliated, the terminal stem presenting nothing remarkable. Mouth 

 situated at a small distance from the point of the insertion of the 

 lower antenna;, and surrounded, as ordinarily, with a rather stout 

 labrmn, a bifid tonguelet, and a pair of mandibles, which are arum 

 on Uicir internal border with somo pointed teeth, and carry a short 

 and flattened palp, divided into three joints. Two pairs of jaws are 

 applied on the mandibles and tonguelet. 



T. Iriaupida is the only species known. Length about 15 lines 

 It was found far at sea, in the Atlantic Ocean, by M. Keynaud. 



M. Milne-Edwards thinks that the genus J'odoprit, or Hammer 

 Headed Shrimp of Thompson, may belong to this family; but hi 

 observes, that it is too imperfectly known to warrant the anignmen 

 of precise characters to it. This cruntacean, which was found in thn 

 Atlantic Ocean, and is phosphorescent, is figured and described in the 

 interesting ' Zoological Researches ' above quoted. 



Lonfr-IIeaded Shrimp (Ittfiftr 7>/>m), mignificd, and of Iti natural itu. 

 (Thorn peon.) 



II. Bicuirassed Slomapoda. [PiiTLLOSOJU.] 



III. Unicuirassed ,Vomn;>o<f<i. 



The abdomen is well developed, and is composed of seven movmhle 

 segments, the last of which constitutes a very large caudal l>Me. The 

 eyes are stout and convex (renflcs) towards the end ; the first pnii- >< 

 antenna) are inverted below and behind their peduncle, and aro com- 

 posed of a cylindrical peduncle formed of three joints and terminated 

 by three filaments, which are ordinarily multinrticulate. The second 

 pair of antenna? are inserted behind and outside tho preceding, anil 

 are provided with a great lamellar appendage fixed on a stout and 

 cylindrical joint, at the extremity of the first joint of their peduncle, 

 which also carries in front a filament, which is ordinarily imiltiarticu- 

 late. The mouth is rather distant from the antennrc, and carried on 

 a nearly triangular eminence, the base of which corresponds with the 

 insertion of the prehensiln feet The upper lip in large, projecting, 

 and semicircular. The mandibles are directed downward*, and ter- 

 minate by two toothed branches, one of which ascends in tho back 

 part of the mouth, towards the stomach ; the palpiform Btem which 

 carries these organs is small and sometimes null. The lower lip is 

 large, and partially covers the extremity of the mandible*. Thn jaws 

 are very small, and applied exactly against the mouth ; the fir 

 terminate by a kind of hook directed inwards, and armed with spine* 



