534 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 83 



HIPPOCAMPUS INGENS Girard 



Figure 55 



Hippocampus ingens Girakd, in Reports of explorations and surveys to ascer- 

 tain the most practicable and economical route for a railroad from the 

 Mississippi River to the Pacific Ocean, vol. 10, pt. 4, Fishes, p. 342, 1859. 

 (San Diego, Calif.) 



Hippocampus gracilis Gill, Proc. Acad. Nat. Sci. Philadelphia, 1862, p. 283. 

 (Cape St. Lucas, Calif.) 



Hippocampus ingens Jordan and Eveumann, U. S. Nat. Mus. Bull. 47, pt. 1, 

 p. 776, 1896. (H. gracilis placed in synonymy of ingens.) 



Hippocampus ecuaderensis Fowler, Proc. Acad. Nat. Sci. Philadelphia, vol. 73, 

 p. 446, fig. 2, 1921. (Bahia, Ecuador.) 



Hippocampus ingens Meek and Hildebrand (in part), Publ. Field Mus. Nat. Hist., 

 zool. ser., vol. 15, pt. 1, p. 256, 1923. (Chame Point and Panama City 

 market, Panama.) 



Diagnosis. — Fii'st caudal segment hexangular^^ (in 10 specimens 

 studied, injured in one); last trunk segment octangular; penultimate 

 trunk segment septangular or novemangular (completely septangular 

 in four and novemangular in four, incompletely novemangular in two) ; 

 antepenultimate and the preceding trunk segments septangular. In 

 other words, an extra plate on first caudal and last one or two trunk 

 segments; or, upper ridges of tail and trunk overlapping on two or 

 three segments. Trunk segments usually 11 (in seven), sometimes 

 12 (the twelfth segment complete in one specimen, incomplete ^ in 

 two; all these three specimens having the penultimate trunk segment 

 with an extra plate). Caudal segments 38 to 40. Dorsal rays mod ally 

 19, varying 19 to 21. Pectoral rays modally 16, varying 15 to 17. 

 Tubercles well developed in medium-sized fish, usually pointed, 

 sometimes rather stubby but high; becoming almost obliterated 

 in largest males, somewhat better developed in large females. 

 Coronet of medium height in medium-sized fish of both sexes and 

 in large females, somewhat lower in large males. Trunk notably 

 slender; snout long. Filaments very few and rather short (present 

 only in the medium-sized specimens examined). Profusely covered 

 with many small rounded brown spots, somewhat as in reidi; small 

 whitish or silvery dots often unusually profuse, characteristically 

 tending to an arrangement into irregular rows and often tending to 

 coalesce into fine white streaks irregularly spreading over nearly en- 

 tire tail, trunk, and head. Dorsal with a submarginal dark streak 

 typically present, often obscure; margin over dark streak hyaline, 

 more or less dusky or difi^usely spotted below the streak; sometimes 

 entire dorsal nearly colorless. (For counts and measurements see 

 tables 1 and 2.) 



" For a discussion of the modiDcation in the structure of the first caudal and posterior trunk segments in 

 the species of Hippocampus and of the various ways in whicli this modification may be expressed, see 

 pp. 505 to 507. 



" See p. 504 for explanation of an incomplete trunk segment. 



