732 



ORDER PERITRICHA. 



Platycola truncata, From. sp. 



Lorica oval, rounded at the base, truncate anteriorly, having no pro- 

 jecting neck, occasionally with a few transverse plicse, the margin of attach- 

 ment slightly expanded in a frill-like manner ; colour yellow ; animal- 

 cule transparent, subcylindrical, posteriorly attenuate, extensile to a 

 considerable distance beyond the margin of the lorica. Length of lorica, 

 1-400". Hab. — Fresh water. 



Platycola striata, From. sp. Pl. XL. Fig. 42. 



Lorica colourless, elliptical, ventricose, one and a half times as long as 

 broad, developed anteriorly into a very short truncate neck, the surface of 

 the inflated body portion ornamented with numerous, usually eight, trans- 

 verse striae, distributed at even distances between the neck and the posterior 

 extremity, the surface of attachment supplemented with a narrow frill-like 

 lamina ; animalcule cylindrical, transparent, surface finely punctate. Length 

 of lorica 1-350". Hab. — Freshwater. 



Platycola gracilis, From. sp. 



Lorica transparent, subcylindrical, about twice as long as broad, rounded 

 and slightly inflated posteriorly, aperture obliquely truncate, not taking the 

 form of a separate neck; surface of attachment expanding in a frill-like 

 manner ; animalcule trumpet-shaped, massive, transparent ; vestibular 

 bristle very conspicuous. Length of lorica 1-400". 



Hab. — Fresh water. 



De Fromentel mentions that the vestibular bristle, in addition to being con- 

 spicuous, is often reflexed in a ring-like form, and so figures it ; from his description 

 and illustration given it would appear that the animalcule possesses a distinct mem- 

 branous lip or collar as occurs in the genera Opcrculana and Lagcnophrys. 



Platycola longicoUis, S. K. Pl. XL. Fig. 35. 



Lorica smooth, evenly ovate, depressed, prolonged at its anterior 

 extremity into a long, narrow, obliquely elevated neck, whose length equals 

 that of one-third of the ovate body portion ; colour varying from yellow 

 to chestnut-brown ; the animalcule projecting when extended to a distance 

 equal to the length of the neck of the lorica from the aperture of that 

 structure. Length of entire lorica 1-200". Hab. — Fresh water. 



This species, as first figured, without an independent specific description, by 

 De Fromentel,* is referred by him to the Vaginicola decumhens of Ehrenberg, from 

 which type, however, it may be at once distinguished by its long obliquely directed 

 neck. Examples of this species have been recently received by the author through 

 Mr. John Wood from the neighbourhood of Dundee. In external contour the lorica 

 closely resembles that of the Heterotrichous form FolUcularia Boltoni previously 

 described. 



* ' Etudes surles Microzoaires,' 1876. 



