28 “TERRA NOVA” EXPEDITION. 
region of the head; this is an expansion of the anterior part of the dorsal 
fin-fold. 
(6) Pigment is wanting, except for a median black spot on the parietal region and 
some pigmented areas on the tail. In specimens of 14 mm. (and less) there 
is a dark area above and another below on the caudal peduncle ; in larger 
ones the dorsal area spreads forward on each side of the adipose fin, and 
the ventral one may disappear, or may be replaced by a median series of 
Distribution of Myctophum antarcticum. Recorded captures of the adult are marked + ; larval 
Fie. 3. 
and post-larval stages taken by the ‘Terra Nova,” ff. The map shows the extreme limit of 
pack-ice ~ ~ ~~~, and the mean annual surface isotherms of 6° C.——-—-—-— and 
12° C. —.—-—-—. 
dark spots, probably the precursors of the infracaudal plates of the adult 
female. 
Examples of 10 to 12 mm. are often more elongate, and have no photophores 
and no pelvic fins ; the adipose fin extends forward to the dorsal; the dorsal fin is low, 
and its rays are undeveloped or just evident. The maxillary reaches only to below the 
anterior part or middle of the eye, which is relatively larger than in the specimens of 
14 to 18 mm., whilst the snout is correspondingly shorter. 
ee ee eS 
