Kingsley.] 
446 
[March 15, 
grntion and decay. In the anterior portion of the tadpole the chan- 
ges are equally important ; at the anterior end of the body is found 
a single swelling, one on each side of the body at about the middle 
point, and at the posterior end, one on each side of the tail. These 
live jmocesses arose simultaneously and were the only ones which 
are constant in position. At the base of each the body becomes 
more transparent and the cellular structure of thin outer walls is 
readily discernable. These processes gradually elongate, the 
anterior one invariably coiling itself in a short spiral. Other 
processes similar in origin and structure soon make their appear- 
ance but there is no regularity in their number or position, ten 
being the largest number seen, while one specimen (fig. 16) went 
through its entire development with only the primary five. The 
subsequent development of these processes may be seen in figs. 
14 to 17 and indistinctly their degradation and absorption in figs. 
18 and 19. 
At the same time with the growth of these processes there de- 
velopes an envelope for the body whose method of origin I was 
not able to make out. The first traces of this envelope were seen 
some little time before the tadpole attached itself. This envel- 
ope consists of an outer transparent gelatinous and apparently 
structureless layer and an inner portion made up of indistinct con- 
centric layers in which are irregularly scattered nuclei. 1 These 
two layers completely surround all of the body and the processes 
with the exception of the tail and not a single opening is visible 
in it at this time. 
When about to become attached the whole of the outer surface 
of the tadpole becomes adhesive and any portion which comes in 
contact with any solid body immediately adheres to it, and the 
attachment seems in our form to be wholly by means of this 
layer. 1 have frequently seen the tail of the embryo become thus 
affixed to the bowl in which the tadpoles were kept, and then in 
spite of the most vigorous wrigglings the embryo was unable to 
free itself, and after some ineffectual efforts it settles down to un- 
dergo the remainder of its transformations. The processes which 
grow out from the body are generally considered as the means by 
which the embryo attaches itself, but in Molgula manhattensis 
l These layers are much more distinct in the drawings then in nature. 
