ON THE ANATOMY OF FISHES. 
203 
Cryptoi^terus micropogon. 
This species very clearly resembles C. micronemci. Relatively to the large lateral 
chambers the anterior one is smaller than in the latter species. The walls of the bladder 
are much thicker than in most other species of the genus, this is principally due to the 
greater development of the inner stratum of the tunica externa. The dorso-lateral 
and venfcro-lateral muscles of the trunk diverge so slightly, that the lateral walls 
of the anterior chamber are entirely excluded from contact with the external skin ; 
the lateral lobes of the liver are also interposed between the two structures. As in 
C. micronema the lateral compartments are prolonged in the form of a tapering caecal 
diverticulum into the anterior section of the tail. The intercalarium has a flattened 
expansion in the interossicular ligament, and also a horizontal process which, without 
forming a proper ascending portion, nevertheless curves slightly upwards into the 
fibrous wall of the neural canal at its inner or vertebral extremity. 
Cryptopterus linipok. 
In this species the relatively small air-bladder is broadly ovate or almost spherical 
in shape and about as deep as it is wide, the greatest depth being coincident with the 
position of the pillar -like transverse septum which occupies the centre of the bladder, 
and is continuous behind with the comparatively short longitudinal septum. The 
lateral walls of the anterior chamber are closely applied to the extremely thin 
external skin. Dr. Gunther (15, p. 40) remarks of this species, that it “appears 
to have the place behind the head, where the air-bladder is seen through the trans- 
parent skin, of a dark colour during life.” Unfortunately the intercalarium had been 
damaged, and we cannot therefore affirm that it is represented by more than an 
interossicular nodule. 
Cryptopterus p)(-demhangensis. 
The walls of the air-bladder, which in this species is otherwise very similar to that 
of C. limpok, are exceptionally thin and diaphanous, and in the lateral regions of the 
anterior chamber are in contact with large blister-like lateral cutaneous areas, thus 
rendering that part of the body more than ordinarily translucent. 
Cryptopterus hicirrhis. 
So far as the air-bladder is concerned, this species closely resembles the preceding. 
The intercalarium, however, not only consists of interossicular and horizontal 
portions, but the latter curves slightly uj)wards into the fibrous wall of the neural 
canal, and there forms a distinct rudiment of an ascending process. 
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