CONTRIBUTION TO OUR KNOWLEDGE OF 
THE MYXINOIDS.! 
JULIA WORTHINGTON. 
INTRODUCTION. 
Ever since Johannes Müller introduced the Myxinoids to the 
scientific world, interest in these primitive forms has continued 
unabated, both as regards their peculiarities of structure and 
function and their consequent position in the vertebrate series, 
and the interrelations of the different varieties among themselves. 
Owing to the wide geographical distribution of the Myxinoids, 
the relative scarcity of individuals, and the difficulty of securing 
material for study, especially the living animals, previous papers 
have been based upon the study of museum specimens, and our 
knowledge has, in consequence, been very incomplete. It was 
my good fortune to obtain, during the summer of 1904, several 
hundred individuals of Baellostoma dombeyi Lac. in sound, 
healthy condition, which I kept alive in aquaria. I was able to 
provide conditions closely approximating their usual habitat, and, 
under these favorable circumstances, I kept them under con- 
stant observation for four months. The observations made have 
been checked by a study of the conditions of their normal habi- 
tat. This paper, therefore, is based mainly upon a study of 
living individuals in conditions approaching as nearly as possible 
the normal environment; and these notes are published in the 
hope of throwing some new light upon this interesting form, and 
for the purpose of correcting some erroneous statements that, 
through lack of means of observation, have gained currency. 
I wish to express my thanks to Dr. C. H. Gilbert, of Stan- 
ford University, who kindly placed at my disposal the facilities 
of Stanford's seaside laboratory at Pacific Grove, California; to 
1 Under the direction of Dr. Howard Ayers. 
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