REVIEW OF HIPPOCAMPUS — GINSBURG 537 



mately the same manner as it differs from guttulatus or multiannularis , 

 in the frequency distribution of its meristic characters it is nearer to 

 the European species than to the American hudsonius (see table 1). 

 As stated, it differs from hudsonius, guttulatus, multiannularis, reidi, 

 and others in tending strongly to have an extra plate on the penulti- 

 mate trunk segment, and as a consequence the upper ridges of the 

 tail and trunk overlap on three segments about as often as on two, or, 

 in other words, the penultimate segment is novemangular nearly as 

 often as septangular. Quite likely this character is an important and 

 suggestive indicator of phylogenetic relationship, in spite of the fact 

 that it is shown only by half, or slightly more than half, of the popula- 

 tion. 



Material examined and geographic distribution. — San Diego, Calif.; 

 A. Cassidy; four cotypes (982).^* Mazatlan, Mexico; J. G. Ortega 

 (86239). Chame Point, Panama; March 8-14, 1913; R. Tweedlie 

 (82038). Panama City market; Meek and Hildebrand (79682, April 

 1912; 79683, 1912; 79684, March 22, 1912). Panama Bay, lat. 7°57' 

 S., long. 78°55' W.; March 5, 1888, Albatross (43404). Salinas, Ecua- 

 dor; September 17, 1926; Dr. Waldo L. Schmitt (88833, in bad condi- 

 tion but evidently the present species). 



Total number of specimens studied, 1 1 ; three with a brood pouch, 

 113 to 201 mm long, seven without any trace of a brood pouch, 87 to 

 158 mm (one specimen broken, sex and length indeterminable). The 

 localities from which specimens were examined represent a range from 

 San Diego, Calif., to Salinas, Ecuador. 



Synonymy. — I follow previous authors in placing H. gracilis in the 

 synonymy of ingens, although the original description is not sufficiently 

 detailed to be certain of such reference. Since the type is evidently lost 

 this is probably the best course to take, unless another species turns up 

 from that region. The account of H. ecuadorensis shows that it was 

 apparently based on a specimen of ingens. Fowler states that his 

 new species "differs from H. ingens in more dorsal rays, larger eye, 

 blunt body and tail rings, and the absence of dermal flaps." The 11 

 specimens examined have 19 to 21 dorsal rays, and it is consequently 

 reasonable to expect that 22 rays, as in the type of ecuadorensis, falls 

 v/ithin the range of variation ; the blunt rings and the absence of der- 

 mal flap are usual in large specimens. The size of the eye is too vari- 

 able to be employed b}'' itself in distinguishing species. The color 

 pattern, as indicated by the description and figure, is typical of 

 ingens. 



" Unless otherwise specified, the numbers given in parentheses throughout this paper are U. S. National 

 Museum catalog numbers. Data without numbers refer to specimens in the U. S. Bureau of P^isherics. 



