SALPA CORDIFORMIS. 183 



The tailed larvae may be picked up with a pipet while swim- 

 ming (the dead ones on the bottom of the dish should not be 

 used), dropped into fixing fluid, and finally stained and mounted 

 in balsam. Some larvae will be found attached to the dish by 

 their adhesive organs. Notice where these organs are sit- 

 uated. 



In larvae that have been previously stained and mounted 

 observe: 



(a) The shape of the animal and its division into body and 

 tail. 



(6) The thick test, and the oral and atrial openings. 



(c) The adhesive organs. How many are there? 



(d) The notochord. How far does it extend? 



(e) The tail muscles. 



(/) The pharynx, with as yet few gill clefts, the endostyk, 

 esophagus, stomach, intestine, and yolk-mass. 



(g) The cerebral vesicle with the eye-spot and otolith. 



If young individuals that have been attached but a short 

 time, but have lost their tails, are stained and mounted, they 

 will be found very instructive when compared with the larva. 

 The complete degeneration of the tail and the final rotation 

 into the position of the adult can be traced in a series of indi- 

 viduals. 



Drawings of an adult individual, of a larva, and of a young 

 individual are desirable. 



Van Name: Compound Ascidians of the Coasts of New England and Neigh- 

 boring Provinces. Proc. Bost. Soc. Nat. Hist., 34, 1910. 



SALPA CORDIFORMIS. 



Examine a specimen in a bowl of water without dissecting. 

 Use a hand-lens. 



Sexual form (occurring in chains) : 



1. Note the transverse muscle bands. How many bands are 

 there? Are they complete or interrupted? Do you know what 

 they are for? 



