PHYLLOPODA. lOJ 



doubtcdly contributed to render the period longer than usual, mtist 

 have been the absence or deficiency of the requisite kind of food or 

 animalcula ; bearing in mind these considerations, it may be stated, 

 that during six weeks the larva retained its original rowers and its 

 sessile eyes, as in fig. 9, while the permanent members were not 

 fully developed ; at the end of two months, dark excrementitious 

 matter first appeared in the intestinal canal, the lateral eyes became 

 pedunculated, the whole of the members were complete, and the 

 great rowers were first converted into horns, and the antennas 

 shewed a considerable degree of elongation, but it required full two 

 months and a half to render the animal perfect, and capable of pro- 

 pagating its species. 



Although many of the Entomostraca will be found to present 

 themselves first under a similarly masked form (Amymone), yet the 

 peculiar changes noticed above are confined to the Phyllopoda with 

 pedunculated eyes, which alone furnish the singular spectacle of 

 Monoculi, Trinoculi, and Binoculi, or in other words, of an animal 

 possessed of one, three, and at length of but two eyes, during the 

 life of the same individual. 



Other Species of Artemis. 



Amongst several minute Crustacea sent me by the Rev. Lans- 

 down Guilding, from the West Indies, was one female probably of 

 this Genus (PL 1, f. 11, 12) ; to that gentleman, after whom I have 

 named it, and who is one of the most zealous and intelligent Natu- 

 ralists the West Indies had ever to boast of, I must leave its natural 

 history. See Explanation of Plate I. for details. 



The Eulimena of Latreille, which Dr. Leach considers a species 

 of Artemis, found in the Mediterranean, seems to require further 

 elucidation. 



The Branchipus Paludosis, (PI. 3, f. 6), I consider as a fourth 

 species of Artemis. ---This, which is a native of swamps in Green- 

 land, attains to the length of three quarters of an inch, has smaller 

 horns than A. Salinus, the tail terminated by a pair of plumose setae, 

 and the oviferous sac of the female of an elongated form. 



Chierocephalus, 



This Genus, instituted by Prevost, is distinguished from Artemis 

 by the very complicated apparatus situated between the basis of the 

 Great Horns in the male (PI. 3, f. 4 and .5, PI. 4, f. 1), and in the 

 horns being much smaller j for details I may refer to Prevost's Me- 

 moir, p. 201, pi. 20, 21, and 22. De-smarest makes this synonimous 

 with B. Paludosis, and it appears to have been confounded with the 

 Branchipus Stagnalis by most authors. This would appear to be 

 the most common and widely distributed of the whole of this pecu- 

 liar tribe : it .seems to be that species first described by Mr. Ed. 

 king, in the Phil. Trans. 1667, vol. .57, p. 72. . 74, being discovered 

 by that gentleman in a ditch near Norwich, and has been more late- 

 ly elucidated by Dr. Shaw in the Linna?an Transactions. In France 

 it has been noticed in the marshes of Fontaineblcau and Bondy, in 

 3 pitches about Meudon near to Paris, and in ditches which border on 

 thejoutc from C'aJttillun to Saintc-Foi,— -Both Shaw and Prevost 



