Charles R. Stockard 487 
rectly, I think, failed to find any correspondence between branchiomery 
and myomery. 
Price, 96, was the first to describe embryos of the myxinoids. He 
studied three stages in the development of Bdellostoma and in the young- 
est embryos found a narrow canal extending from the anterior end of 
the mouth cavity into the cavity common to the nose and hypophysis, 
while in the older stages this canal was closed. M. Fiirbringer saw in 
this observation very strong evidence in favor of Dohrn’s idea that the 
primitive mouth of vertebrates is represented by the hypophysis. - 
Price, working with a limited supply of material made the mistake 
of supposing that a great number of gill pouches appear during develop- 
ment, possibly as many as thirty-five. Of these, he thought the posterior 
ten or fourteen develop into the gills of the adult while the others entirely 
disappear. Dean corrected this statement when he found a shifting and 
not a closing of the gills to take place; and Price himself, in a subse- 
quent paper on the development of the excretory organs of Bdellostoma, 
based on a more complete series of embryos, has corrected his former 
statement and accepted Dean’s interpretation on this point. Notwith- 
standing these corrections Price’s original idea has since been utilized by 
Ayers and Jackson, 00, who try to account for the atrophy of the for- 
ward gills as due to the enormous development of the “club muscle” 
in that area. Johnston, 05, also quotes Price’s earlier conclusion and 
states his belief that there is a reduction of the anterior gills on account 
of the parasitic life of this animal. It has been clearly shown, how- 
ever, by Howes, 91, Ayers, 93, Jordan and Everman, 96, and Worthing- 
ton, 05, that these animals are not parasitic but predaceous, attacking 
disabled fishes. Therefore Johnston’s explanation will not suffice. Since, 
also, there are no forward gills lost we must accept the position that the 
gills belonged originally to the head region, and owe their extension into 
the trunk to the shifting forward of trunk myotomes into the occipital 
region, the view, by the way, which Johnston rejected in favor of his 
explanation cited above. All of these various disagreements concern- 
ing the development of the myxinoids have come within the last few 
years; Price’s initial work on the subject appearing in 1896. It may be 
mentioned that only a few workers, about half a dozen in all, have been 
so fortunate as to obtain the material. 
This review of the various and contradictory opinions might easily 
be extended, for no author has seemed to consider his paper complete 
without taking a new position regarding either the significance of this 
group of Marsipobranchii or the importance of the evidence furnished 
