XXII CATOSTEOMI 635 
Syngnathus, Penetopteryx, Nannocampus, Stigmatophorus, Hippo- 
campus), in a groove under the tail (Phyllopteryx), or in a groove 
on the abdomen (Doryichthys, Coelonotus, Nerophis, Gastrotoceus). 
Fic. 387.—Iippocampus guttulatus. 
Male, showing brood-pouch (mp). Fic. 388.—Phyllopteryx eques. 
a, Anus; 6.a, branchial aperture. 3 nat. size. 
An Australian species of Syngnathus has been described by 
E. P. Ramsay under the name of S. intestinalis, from its living 
inside Holothurians, in the manner of Fierasfer, and G. Lunel has 
observed a Doryichthys to offer a similar instance of inquilinism. 
One of the most remarkable types of Syngnathids is Phylloptery2, 
from Australia. The spines and knobs of the head and body are 
furnished with dermal appendages, which closely imitate the 
fucus among which they live. 
Fam. 11. Pegasidae.—bBody short or moderately elongate, 
encased in an exoskeleton forming rings. Anterior vertebrae 
not elongate; no ribs. Snout produced beyond the mouth, 
which is small, inferior, and toothless; no praeoperculum, no 
symplectic ; gill-opening very small; gills pectinated. A single 
dorsal fin. Pectoral fins large, horizontal; ventrals reduced to 
one or two filamentous rays, behind the scapular arch.  <Air- 
bladder absent. 
