50. niPPOCAMPID^. 3^5 



wiso essentially as in S. californicnfic. Nuchal plates someuiuit keeled 

 iu var. leptorhynchus ; not keeled in var. arundinaceum. Coast of Cali- 

 fornia, cbieti.v south of Point Coucepeion ; abundaiit. 



{Siingnalhus hptorhynchus Girard, Proc. Acad. Nat. Sci. Phila. 1854, 15r>: Si/n/jndlhus 

 hjytorh ;) n chus Giravd, U. S. Pae. R. R. Surv. Fisli. :i\G: S;/nfjttathitii Icjilorhniichn-'i Gill, 

 Proc. Acad. Nat. Sci. Pliila. 1862, 284: Si/nguathus (irundiHaccHs Girard & Gill, 11. cc.,) 



aa. Breast shields covered by loose skin; lower jaw iucluded. {D^nnniustcthus* Gill.) 



61§. S. peiBictipiiiiBe (Gill) J. & G. 



Brown ; dorsal fin speckled. Body comparatively robust Snout 

 moderate, a little longer than the rest of the head. Eye large. Occiput 

 with a raised keel ; joint between the occiput and the first dorsal shield 

 more perfect than usual, so that the head can be placed at an angle with 

 the body. Greatest depth about equal to length of i^ost-orbital part of 

 head. Skin on breast and anterior ventral plates thin, showing the 

 striation of the bones. Tail twice as long as trunk. Head 8; D. 41 ; 

 rings 19+39. L. 12. San Diego, Cal. Only the original types known. 



(Dermatonft'thus 2)unctipintiiif Gill, Proc. Acad. Xat. Sci. Pliila. 1802, 283.) 



Family LIX.— HIPPOCAMPIDJE 



{The Sea Horses.) 



Syngnathoid fishes destitute of caudal and ventral fins, and with the 

 tail iirehensile. Form of the body and head singular; in the typical 

 genera the body is compressed, and the head, which is placed nearly 

 at right angles with the axis of the body, is surmounted by a bony 

 crest. These little fishes have thus a remarkably horse-like physiog- 

 nomy, like that of the conventional "knight" at chess. Mouth very 

 small, terminal. Dorsal fin median, of soft rays only; anal fin minute; 

 pectoral short, with a broad base. Gill-openings very small. Egg-pouch 

 of the male usually at the base of the tail. Genera about 4 ; species 

 about 30, most of them belonging to Jlippocampus. Fishes of the open, 

 seas of warm regions. They attach themselves by their tails to sea- 

 weed and other floating substances, and are often carried to great dis- 

 tances by currents. 



{Sjngnathidx, group Illppocampina Giiatlier, viii, 194-206.) 



a Body compressed ; occiput with a narrow bony crest, which is surmounted by ai 

 "coronet" ; shields with tubercles or spines Hippocampus, 188. 



"Gill, Proc. Acad. Nat. Sci. Phila. 18G2, 283: type Dermatoatethm pumUpinnia Gill. 

 {defj/iux, skin; 6rcOoi, breast.) 



Bull. Nat. Mus. '^o. IG 25 



