Rev. A. M. Norman on an undescribed Crustacean. 429 



T. Perroteti. PI. VII. figs. 5, 6, 7. 



Psammophis Perroteti, Dura. & Bibr. vii. p. 898. 

 Dryophis tropidococcyx, Gthr. Catal. Col. Snakes, p. 157. 



Brownish -green; without epidermis, green (Dryophis); a 

 whitish line along the side of the belly (Dryophis). Upper 

 labials eight, the fourth and fifth * coming into the orbit. One 

 anterior and one posterior ocular. Scales in fifteen rows. 



Hab. Madras. 



LV. — On an undescribed Crustacean of the Genus Mysis. 

 By the Rev. Alfred Merle Norman, M.A. 

 [With a Plate.] 

 Three members of the genus Mysis are described in 'Bell's 

 British Crustacea/ Since the publication of that work, the 

 number of British species has been doubled. In the year 1853, 

 Mr. Gosse described a new form in this Journal under the name 

 of Mysis productusf. In the spring of 1855, I met with two 

 additional species in rock-pools at Falmouth ; and these were 

 described the following year by Mr. R. Couch, who had taken 

 them at Penzance J. The six above-mentioned species, together 

 with that now to be characterized, may be divided into the 

 following sections : — 



A. Telson (central lamina of the tail) with the apex bifurcate. 



Mysis flexuosus, Miiller; Mysis Lamornce, R. Q. Couch; 

 Mysis Spiritus, n. s. 



B. Telson with the apex entire. 



Mysis vulgaris, J. V. Thompson ; Mysis Oberon, R. Q. Couch ; 

 Mysis Griffithsia?, Bell; Mysis pro ductus, Gosse. 



It will be necessary, in order to draw attention to the distin- 

 guishing characteristics, to describe the species of the first section. 



Mysis flexuosus, Miiller. PI. VIII. figs. 2 & 3. 



Cancer flexuosus, Miiller, Zool. Dan. vol. iv. p. 34, tab. 66. 



Mysis spinulosus, Leach, Linn. Trans, xi. p. 350 ; Desm. Consid. p. 242 ; 



M.-Edw. Crust, ii. p. 457. 

 Praunus flexuosus, Leach, Ed. Enc. vii. p. 401. 

 Mysis Chamteleon, J. V. Thompson, Zool. Researches, p. 28, figs. 1-10; 



M.-Edw. Crust. 457 ; Bell. Brit. Crust, p. 336 ; White, Pop. Hist. Brit. 



Crust, p. 143. 

 Mysis Leachii, J. V. Thompson, Zool. Researches, p. 27. 



Mysis albescens, cinereus, viridis vel brunneus. Thorax cylindricus. 



* My former statements, that the third and fourth (p. 157) or the fifth 

 and sixth (p. 158) upper labial shields enter the orbit, are erroneous, 

 t Ann. & Mag. Nat. Hist. 2nd ser. vol. xii. p. 156, pi. 6. fig. 5. 

 % The Zoologist, vol. xiv. (1^56), pp. 5284-5288. 



