South American Rotifer a. By J. Murray. 235 



Notes on the Species. 



Philodina vorax Jan son (-/-). — The type occurred in Bolivia 

 and Brazil, and in Bolivia there was also a variety here ligiired 

 (Plate IX, figs. la-Id). The chief peculiarity is in the spurs, the 

 membrane connecting which is notched in the middle line, whereas 

 in the type it is unbroken. 



When the animal is crawling, the anterior part of the trunk is 

 widest, having a barrel-like swelling such as has been noted in 

 several other Bdelloids {Rotifer irisecatus, etc.). I do not know 

 whether the character has any value, or even if it is permanent. 



Habitat. — Santa Cruz, Tuichi Valley, Bolivia. 



Philodina americana sp. n. Plate IX, figs, ha-bd. 



SpecifiG Characters. — Of medium size ; pale yellow, alimentary 

 tract orange-red ; all papillose-punctate ; deeply plicate, wrinkles 

 forming symmetrical pattern on central trunk. Rostrum very 

 short, lamellae small ; neck with two very large dorso-lateral 

 prominences ; length of antenna three-fifths of neck width. Jaws 

 very narrow, triangular, teeth 3/2. Pre-anal segment short and 

 broad, anal twice as long ; foot very short, three- join ted ; spurs 

 short and obtuse, nipple-shaped. Brain very small, triangular. 

 Ventral toes larger than dorsal. No eyes. 



Length, fully extended, 300 /x ; width of trunk 90 /x, across 

 neck prominences 55 yu,, pre-anal 60 yu-, across spurs 20 yu, 



The animal was never seen to feed, but it possesses so many 

 good characters that it should be easily recognized by the careful 

 student, and I think we may justify the naming of it without 

 knowing the form of the corona. Such large neck-processes are 

 only known among Bdelloids in Pleuretra africana (2o), such 

 narrow jaws only in CaUidina natans (17), and some HabrotrochcV, 

 such blunt spurs only in Philodina flaviceps, but those of P. ameri- 

 cana are divergent, of P. Jiamceios parallel. 



Hahit-at. — In moss from trees grrowino; on the river bank at 

 Tigre, near Buenos Ay res, Argentina, March 1912. 



Phil:odi7ia sp. (undescribed). 



For description and figure see paper on '' Some African 

 Rotifers " i^U) J.R.M.S. 1911, p. 4, Plate I. figs. 2>a-6e. 



This fine large species, which is remarkable for its resemblance 

 to a species of another genus, Mniohia russeola, occurred in Bolivia 

 and Brazil. 



The Bolivian form is smaller than that found in Africa, and 



