140 
CHONDROPTERYGII. 
481. Syngnathus zanzibarensis, sp. n. Plate XX. fig. 5. [312, 381.] 
The length of the head in adult specimens is contained from ten to eleven times, and 
in immature specimens from eight to nine times in the total length. The length of the 
snout equals the distance from the anterior margin of the orbit to the extremity of the 
pectoral fins when laid backwards ; it is scarcely compressed, and not much higher than 
broad. The diameter of the orbit is one-seventh of the length of the head, the space 
between the eyes is concave and less than the diameter of the orbit. Occiput some- 
what elevated, without being raised into a ridge. Opercles swollen, without ridge, and 
nearly smooth. Trunk heptagonal, slender, twice and a third as long as the head, and, 
measured from extremity of snout to vent, half the length of the tail. The stomachic 
region is slightly thickened. There are twenty-one pairs of shields between the head 
and the dorsal fin, and as many between the throat and the vent. Tail tetrahedral, 
tapering, but not terminating in a point; the width of the upper surface is three- 
fourths of that of the lower one ; the former is slightly, the latter distinctly concave. 
It has from fifty-nine to sixty-three rings, of which eighteen are occupied by the 
membranous egg-pouch in the males. The base of the dorsal is equal to the length of 
the snout, measured from the centre of the eye ; it stands on three body- and three 
tail-rings, and consists of twenty-six rays, the length of which is less than the height of 
the tail beneath the last ray. Caudal very minute, more distinct in young than in adult 
examples. 
Colour brown, marbled and punctulated with lighter and darker; young specimens 
have about thirteen broad brown cross bands, at equal distances, occupying the whole 
of the lower surface of the trunk. — Length from 4 to 13 inches. 
Zanzibar. 
482. Syngnathus mossambicus. [311.] 
Syngnathus mossambicus, Pet. Wiegm. Arch. 1855, p. 2 77. 
The description of this fish given by Peters agrees perfectly with our specimens, 
except that the head would appear to be relatively about twice as long ; he states 
that in a specimen 140 millimetres long, the head was 7 millimetres only ; we suppose 
• that this is a misprint for 17 millimetres. 
Zanzibar. Mozambique. 
Order CHONDROPTERYGII. 
STEGOSTOMA, Mull. & Henle. 
483. Stegostoma fasciatum. 
Seba, iii. p. 105, t. 34. no. 1. 
Squalus fasciatus, Bl. t. 113. 
[132, 721, 513.] 
