1909.J 



R. E. lyi^OYD : 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 pseudobranchiœ. 



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 ]aw. The pre- 

 maxiha 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. 



A C 



Fig. 3.— Viscera of Mulichthys : 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 cœca. 

 There is no air-bladder. 



