100 ICHTHYOLOGY 
the first dorsal are rather obscure. I have several specimens 
which measure about two inches and a quarter. 
PRI ACANTHUS BLEEKERI. 
Form oval, very compressed ; the anus is placed nearer to 
the extremity of the snout than to the base of the caudal. 
Height of body two and eight-tenths times in the total length; 
head three times and a quarter in the same ; eye twice in the- 
length of the head • lower jaw much longer than the upper 
one, and forming a prominent chin ; maxillaries extending a 
little further than over the first third of the orbit • body and 
head entirely covered with very minute and rough scales ; 
prseoperculum serrated and armed with a very strong acute 
spine at its lower angle ; this spine extends further backwards 
than the margin of the operculum, and this is serrated on its 
inferior part, and forms a strong angle over the insertion of 
the pectoral. The lateral line follows the profile of the back, 
and is formed by a succession of rather larger and keeled 
scales. Dorsal with ten spines ; the first is much shorter than 
the second, and this a little more so than the third, which is the 
longest, and from thence, the others go gradually decreasing in 
height ; they are all very finely barbed on their margins. The 
soft rays number eleven, and are longer than the last spines ; 
caudal rounded, of seventeen rays (in counting one strong but 
shorter one on each side) and of several small ones. Anal formed 
of three strong spines, these are arched and nearly equal in 
length, the last being somewhat the longest and broadest ; the 
first and third are striated and barbed; the rays number 
thirteen and are similar to the dorsal ones. 
The ventrals are very large, composed of a strong crenulated 
spine and of five rays ; this fin extends over the base of the first 
of the free spines I mentioned. The pectorals are small, formed 
of two single spine-like rays, the first of which is short and of 
fifteen rays ; the dorsal and anal are received in a deep sheath 
of the back ; the teeth are viliform and very small on the upper 
iaw ; on the lower one they are larger, conical, disposed on 
one series and rather far apart, one from the other. 
