428 The American Naturalist. [May 
in form which certain members of these groups pass through in 
their development. There are certainly many remarkable genera 
of these animals found nearer home, of the young of which little 
is known, but I aspired to trace the changes in the external form 
of the body of the young of those of which we know next to 
nothing, since many of these animals are more numerous at 
Grand Manan than elsewhere on our coast. The study of the 
Echinoderms, and the desire to trace the development of certain 
genera, are subjects which have interested me for several years, 
and these studies can be pursued with great advantage on the 
shore of Grand Manan. No locality on the coast is more prolific 
in Echinoderm life than this, and here occur animals the problems 
connected with which rank among the more interesting of those 
presented to the consideration of the morphologist. 
Looking, for instance, from the embryological standpoint, we 
have of starfish the genus Hippasterias, of the young of which 
nothing is known. Pteraster, also found in these waters, carries 
its young in pouches on the back or aboral side of the body. It 
presents interesting problems of the nature and significance of 
direct development. Among these animals, with the exception of 
a pair of figures of a single stage of the young, nothing is known 
of the embryology of this marvelous genus. Then there is 
Ctenodiscus, whose young havea strange projection on the middle 
of the dorsal region of the body, reminding one of the stem of a 
Crinoid. Of the young of Solaster and Crossaster we know 
nothing. Moreover, the affinities of the latter with Brisinga, which 
has likenesses itself to the Ophiurans, are such that a study of its 
young promises interesting morphological results. 
Although many points which I hoped to investigate I was un- 
able to make out, my visit was not wholly without valuable 
results. 
My search for the Comatula described by Stimpson from Grand 
Manan was without success. Familiar with the places which 
this animal loves on other coasts, I looked in similar localities 
along the shore, among the laminarians on the Fucus, every- 
where, but always with disappointment. I gave it up at last, and 
concluded that the specimen which he found was a straggler from 

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