26 



The two species are, however, strikingly difterent in several re- 

 spects, particularly in the number and length of the tentacles. Nei- 

 ther We Id on nor Morgan state anything concerning the number on 

 the Bahama species. However, from Morgan's figures 10, 11, and 

 13, which show in each case portions only of the rows of tentacles, it 

 is certain that they are at least five or six times more numerous in 

 this latter larva than in the Santa Catalina one. Here there are never, 

 so far as I have seen, more than six in each half loop that extends 



backward from the re- 

 ^^^- 1- gion of the apical plate, 



i. e. , from a io b fig. 1. 

 (I should say, perhaps, 

 that the general course 

 of the bands does not 

 differ in any essential 

 respectfrom that of other 

 species.) 



Concerning the 

 length of the tentacles 

 in the Bahama form, 

 Morgan speaks of the 

 ciliated band as being 

 »drawn out into tentacle- 



,-, „ . ^ c. ^■, T ^ ^ m ■ p ü^e proccsscs , hanging 



öuriace view ot a iully deveJoped lornaria, seen irom -i ^^^ r • c 



the left side, but partially also from the front and an- ^"^^^^1 l^ke a fringe from 

 terior. a termination at the apical plate of the inner the surface of the larva», 

 limbs of the longitudinal ciliated band, b posterior His figures show the 

 apex of the loops of the longitudinal ciliated band, longer ones to be seven 



e.s Eye spots. V secondary loop in the transverse, post- 



or eight times as long as 



oral portion of the ciliated band, m position of mouth. 



t.p tentacular processes of the bands. ^^^y are thick. As seen 



by fig. 1 , the processes 

 of the species here under consideration are in no way fringe like, they 

 being mere stubbs, scarcely longer than thick. 



These differences in number and length certainly cannot be due 

 to differences in age , since I have described them as they are in the 

 larva just before its metamorphosis. 



The processes are outpocketings of the ectoderm, and hence con- 

 tain a cavity which communicates with the blastocoel, as can be 

 readily seen upon sections. There are several minor differences 

 between the arrangement of the bands here and in the Bahama 

 species , but for the present brief description I will mention only two 

 of them. 



