,o8 G. A. ELRINGTON 



supposition that the so-called brain cells of Claparede are in reality ova, 

 and he further ascribes the fact of the worm inhabiting a transparent tube 

 to mimicry, a fact which he signalizes by giving the worm the spécifie 

 name gonotheca. 



NoRDENSKiOLD ( 1 90 1 ) adopts Giard's opinion concerning the nature of 

 thèse cells, and states that they are ova, but at the same time he points eut 

 that the animal possesses many larval characters, and he further adds that 

 although he examined very many individuals of the species he never found 

 any maies, that is to say he never found any individuals which did not 

 possess thèse curious cells. 



Taking thèse facts into considération, Nordenskiold refrains from 

 adopting unreservedly Giard's opinion that the so called Wartelia is a 

 distinct species. 



We may mention hère that neither Giard nor Nordenskiold give any 

 reason for asserting thèse cells to be ova, with which they possess few 

 points in common. 



The reasons we hâve for believing thèse cells to be of a glandular 

 nature, are based not only on their structure, but more particularly on 

 their reactions to certain stains. The gênerai appearance of the gland is 

 that of an aggregate of large pear shaped cells, fig. 4, 5, 6, the thin ends 

 of which are directed upwards and forwards in the dorsal direction, and 

 converge so as to form an opening in the middorsal line near the anterior 

 end of the body. The position of the gland in relation to other structures 

 will be seen b}' referring to fig. 4, which represents a horizontal section of 

 the larva. In front of the gland is a mass of nerve tissue forming the cérébral 

 ganglion, whilst fast behind are the first pair of nephridial organs, and the 

 anterior septum. 



The dorsal aperture of the gland is shown in transverse section in 

 FIG. 5. In the same figure two large cells are shown lying one on either 

 side immediately beneath the body wall. 



Thèse cells are of the same nature as those constituting the dorsal 

 gland, but do not form part of it, but open independently at the anterior 

 end of the body on either side of the mouth. 



Finer structure. The cells présent a reticular structure, the network 

 varying in density in différent cells, in some instances a cell appears to be 

 almost empty. The nucleus, fig. 6, nu, is a small round body having the 

 appearance more of a nucleolus than of a nucleus, a condition which we 



