562 



Chiaji, and Mr. A. Agassiz fully confirmed tht suggestion, giving 

 an account of the intermediate stages between the larval and adult 



The Tornaria (Fig. 220 2 after A. Agassiz) seems in many re- 

 spects like some cchinoderm larvae, differing from any yet known, 

 however, in having an organ, the so-called heart (h) situated at 

 the base of the canal leading from the water system to the dorsal 

 pore. The water system is very fully developed. Mr. Agassiz 

 s;iys that the natural position of Tornaria in the water while mov- 

 ing, is usually with the eye-specks uppermost. "They revolve 

 quite rapidly upon their longitudinal axis, and at the same time, 



Fig. 220. 



inclining this axis, advance by a motion of translation, or revolve 

 upon either of the extremities as a fulcrum. Previous to the 

 transformation of Tornaria it is quite transparent ; the brilliant 

 carmine, violet or yellow pigment-spots are closely crowded along 

 the broad belt of anal vibratile cilia, as well as smaller spots on 

 the longitudinal bands of smaller cilia. The eye-specks are black 

 and extremely prominent. The large and powerful cilia of the 

 broad anal belt move comparatively slowly, more like the cilia <■»' 

 the embryo of mollusks, as has already been observed by Mailer. 



The Tornaria soon throws off its disguise of a young Kdiiii'>- 

 derm, and now begins its strange transformations. Previous to 



