350 Mr. O. A. Sayce on a 



which much more closely agrees witli that of M. hricemi, 

 ramely tlftit figured by de Winton as being the skull of his 

 Pudua mej)h{sto2iheJes *. Since Mr. Soderstrom sent the 

 first and typical specimen of P. mepldstojyheJes he has been 

 good enough to present two further exaniples to the British 

 Museum, and these show that some mistake must have 

 occurred in the allocation of the skull Mr. de Winton 

 described. For the skulls of the fresh specimens, about 

 which there can be no question, are very like that of 

 P. pudu in most particulars, and show that mephistoplieles^ 

 although a perfectly distinct species, is not so widely different 

 from P. pudu as Mr. de Winton sup|)osed. Curiously enough, 

 like that figured, the true mejMstopheles skull has a broad 

 naso-premaxillary articulation, and, in addition, diffei'S from 

 that of P. pudu by the almost entire absence of the lacrj^mal 

 pit so well marked in the Chilian form. 



On the other hand, the skull wrongly supposed to be that 

 of P. mephistopheles is closely similar to that of Mazama 

 Iricenii, and indicates the existence in Ecuador of a highland 

 Brocket allied to, and perhaps identical with, the animal now 

 described from Venezuela. 



LVII. — Description of a netv remarhahle Crustacean loith 

 Primi'ive Malacostracan Characters. )iy O. A. SaycE f. 



(Read before the Field Naturalists' Club of Victoria, 8th October, 1907.) 



The new crustacean, of which I now offer a preliminary 

 description, is a very important one, having in a mnjor degree 

 the character of the stalk-eyed forms, although possessing 

 definitely sessile eyes, and also bearing other features which 

 .<^hed additional light on divergent groups. I consider it the 

 most primitive sessile-eyed Malacostracan hitherto recorded. 

 Its nearest ally is undoubtedly the stalk-eyed Anaspides 

 tastnanice, G. M. Thomson. 



It has been easy to separate crustaceans, apirt from the 

 more primitive forms, such as the Entomostraca, into two 

 divisions — one, possessing movably stalked eyes, Podoph- 

 tlialma, and another, with sessile eyes, Edrioi)lithalma — and 

 hitherto there has been no sharp merging of one into the 



* P. Z. S. 1896, p. 510, figs. 2 Sc 4. 



t From the ' Victoriau Naturalist,' vol. xxiv. no. 7 (November 7, 1907), 

 pp. 117-120. 



