I909.J 
R. K. Lloyd: Deep-Sea Fish caught by the ^'Investigator." 
^57 
papillae. Differs from Tetragonurus in that the soft dorsal and anal fins are continued 
nearly as far backwards as the caudal, the anal fin being preceded by three spines ; in 
having only three branchiostegal rays ; in being devoid of gill-raker-like knobs below 
the pseudobranchiae. 
The pectoral arch (text-fig. 2) is suspended from the skull; the coracoid is foram- 
inate ; there is no mesocoracoid ; there are fourmetapterygials, 
the highest is nearly suppressed, the next two articulate with 
the scapula, the lowest and largest touches both scapula and 
coracoid. One or two of the uppermost rays of the pectoral 
fin articulate with the scapula ; the postclavicle is well-devel- 
oped, its lower end is close to but does not touch the hinder 
end of the pelvis. 
The eye rests upon a concave lamina of bone which 
projects inward from the suborbital. The maxilla does not 
make up any part of the margin of the jaw. The pre- 
maxilla and the dentary bear a single row of minute peg-like 
teeth which are set close together in the gum, but scarcely 
project beyond it and combine to form a weak cutting edge. There are a few small 
teeth on the vomer and palatines. 
There are four gill-arches and a wide slit behind the fourth. 
Fig. 2. — Shoulder-girdle 
of Mulichthys. 
Fig. 3* Viscera of Mulichihys : A, from above; B, from left side. C, transverse section of gizzard. 
The pseudobranch is very well developed, consisting of twenty distinct folds. The 
oesophagus is dilated laterally, forming a kind of gizzard which is lined by a hard 
papillated membrane (text-fig. 3). There are numerous well-developed pyloric cæca. 
There is no air-bladder. 
