296 THE AMERICAN NATURALIST. [Vol. XXXVII. 



lack of pigment in the mid-dorsal line becomes a prominent 

 character of the newly hatched young (larval coloration), Aside 

 from this we have had no detailed knowledge of the coloration 

 of hag-fishes, and we could not, therefore, answer the question 

 whether albinos, common in many and widely separate lines, 

 occur also in this phylum of lowly chordates and whether mottled 

 colors had already been evolved. In the event of mottled colors 

 occurring in a single species one might justly infer that the 

 blacks and violets and grays of this group are in reality but 

 symptoms of a deep-water, or possibly of a nocturnal habit. 



In regard to the first of these questions we may now, however, 

 state definitely that true albinos occur among hag-fishes, and that 

 partial albinos are not rare. A perfect albino of H. burgcri, Fig. 

 1, was collected at Misaki, Japan, but it was the only one observed 

 in upward of 800 examples. 1 A specimen of H. stouti in part 

 albino, white from snout to gill region, somewhat mottled where 

 the white passed into the purple body color, Fig. 2, had formerly 

 been observed by me at Monterey, Cal. (1899), together with 

 several less perfect cases of the pigmentless condition, — these 

 out of many hundred specimens collected. So one can justly 

 conclude that in the myxinoid line albinism already plays its 

 usual role among chordates. 



The matter of motley coloring in hag-fishes is also elucidated 

 rather strikingly in the case of a specimen of H. polytrcma 

 Girard, in excellent condition, which the writer recently received 

 from the neighborhood of Valparaiso, Chile. 2 Fig. 3. The col- 

 oration of this species as far as one can determine from a single 

 specimen, is brilliantly mottled with black, ashen, umber and 

 ochre, to a degree which at once causes one to wonder whether 



