its Diatrihution on the British Coasts. 81 



only example of this species in the British Museum eollcc- 

 tiou in 1907, but since then Mr. Boulenger has obtained 

 sj)ecimens from Brittany, and in May of the present year 

 ]\Jr. J. O. Boriey brouj^ht me one taken in Rye Bay, Sussex ; 

 (juite recently ^fr. Anthony Beit has sent for identification 

 a phot()gra[)h of another example, ca|)tured oil' Hastings last 

 Fel)ruary ; with Mr. Jielt's kind permission I am using the 

 photograph to illustrate this paper; it represents a specimen 

 about 18 inches long and 11 wide. 



Raid undulata is so noticeable on account of its character- 

 istic markings, and so different in appearance from our 

 other English Rays, that it is difficult to believe that it 

 occurs regularly on our southern coasts and has liitherto 

 ])een overlooked ; the alternative is to suppose that it has 

 extended its range to the coast of Sussex only in the last 

 few years. 



R. undulata is closely related to R. clavata, differing 

 especially in coloration and in the greater smoothness and 

 more rounded form of the disc ; the teeth are not quite the 

 same and are nearly alike in both sexes ; a full description 

 follows. 



Rata undulata. 



Riiia umhilata, Lacep. Tlist. Nat. Poiss. iv, p, 675, pi. xiv. fis'. 2 

 (1802); Mull. & Henle, Plagiostom. p. 134 (1841) ; Dumeril, Hist. 

 Poiss. i. p. 538 (1805) ; Moreau, Poiss. de France, i. p. 434 (1881). 



Maia mosaica, Lacep. /. c. pi. xvi. tig. 2, 



Disc broader than long; anterior margin slightly un- 

 dulated; extremity of snout projecting as a short process, 

 broadly rounded in the young, pointed in the adult; outer 

 angles of pectorals rounded. Vent nearly equidistant from 

 tip of snout and end of tail (adult) or nearer the former 

 (young). Length of snout (praeocular) about i the width 

 of disc ; interorbital widtii 2| (adult) to 2^ (young) in 

 length of snout, about equal to length of eye and spiracle ; 

 diameter of eye l.\ to 2 in interorbital width. Internasal 

 width § to I (young) or more (adult) of distance from end 

 of snout to fold connecting nasal valves. Teeth close-set, 

 keeled, the middle ones small, pointed in adults ; 36 to 48 

 rows in the upper jaw. A border of asperities along 

 anterior margin of lower surface, not extending to angles of 

 pectorals, present except in very young ; lower surface 

 otherwise quite smooth ; upper surface nearly smooth iu 



Ahu. ii- May. X. Hist. Ser. 8. Vol. si. 6 



