GENUS HAPTOPHRYA. 



569 



This form, selected by Stein as the type of his new genus Haptophrya {Disco- 

 phrya), is identical with the Opalina planarianim of Siebold and the Opalina poly- 

 morpha of Max Schultze. In the original illustrations of this species given by 

 the last-named authority,* and reproduced in the accompanying woodcut, the aceta- 

 buliform organ, as delineated most distinctly at Fig. 2, forms a complete circle and 

 is not bordered with cilia of conspicuously larger size than those which clothe the 

 general cuticular surface. The body is also seen, from Figs, i and 2, to exhibit in 

 its fully developed state a remarkable disparity of size in different regions, the 

 part succeeding the anterior disc-like organ being much strangulated and neck-like. 

 The endoplast is represented as a small, granular, ovate body, located close to the 

 posterior extremity. 



Haptophrya planariarum, Siebold sp.— i and 2. Adult, fully extended animalcules in dorsal and lateral aspect. 

 3. Undeveloped zooid ; «, endoplast or nucleus ; c, canal-like contractile vesicle ; ac, acetabulum. X 250- (After 

 Max Schultze.) 



Haptophrya gigantea, Maupas. Pl. XXXII. Figs. 14 a\d 15. 



Body elongate, cylindro-conical or wedge-shaped, tapering from the 

 front backwards, a little over twice as long as broad ; the anterior extremity- 

 depressed, about twice the breadth of the posterior region, provided with a 

 circular adhesive disc; the ectoplasmic layer or cuticle longitudinally 

 striate, but non-contractile, thickly clothed with fine, short, vibratile cilia, 

 which are disposed in close-set longitudinal rows ; cilia of somewhat larger 

 size bordering the inner margin of the adhesive disc ; contractile vesicle 

 canal-like, irregularly sinuous, extending from the adhesive disc to the 

 posterior extremity of the body ; endoplast elongate ovate or ellipsoidal, 

 freely movable within the internal parenchyma or endoplasm. Length 

 1-25". Increasing by multiple transverse segmentation. 



Hab. — Intestine oi Bitfo panthcrinus and Discoglossus pictus, Algiers. 



This fine Opalinid, first discovered and described by M. E. Maupas t in connec- 

 tion with the hvo above-named Batrachians obtained from Algiers, has been found 

 more recently by M. A. Certes % inhabiting examples of Biifopantherinus, derived from 

 the neighbourhood of Constantine. Through the independent investigations of these 



* ' Ein Beitrag zur Naturgescliichte der Turbellarien,' Greifswalde, 185 1. 



t ' Comptes Rendus,' Ixxxviii. p. 921, 1879. 



% ' Bulletin de la Societe Zoologique de France,' torn, iv., 1880. 



VOL. II. 



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