L. R. GARY. 



At both the anterior and posterior ends of the body there is 

 a depression lined with cilia. The depression at the anterior end 

 has at its bottom an opening communicating with the interior. 



FIG. I. Larva in the active expanded condition, X 3- 



In swimming, the larva rotates rapidly on its long axis, and 

 the anterior end describes a small circle about the axis of pro- 

 gression so that the larva advances by a kind of corkscrew 



FIG. 2. Same larva as in Fig. i, when contracted, X45- 



movement, such as has been described for the larva of Astroides 

 by Lacaze Duthiers l and for Rcnilla by E. B. Wilson. 2 



1 Lacaze Duthiers, H., " De Development des coralliaires," Archiv Zool. exper. 

 et gen., Tom II., 1873. 



* Wilson, E. B., "The Development of Renilla," Phil. Trans. Roy. Soc. Lon- 

 don, Vol. CLXXIIL, 1883. 



