new Forms of American Rotifera. 631 



riorly placed, ventrad to the stomach and intesthie ; foot- 

 glands long ; lateral canals and flame-cells numerous, but 

 apparently without contractile vesicle ; movements rapidly 

 swimming by means of the auricles or writhing with inde- 

 scribable contortions. 

 Length about j4^q inch. 



Masiigocerca spimgeruy sp. n. (PI. XIV. fig. 6.) 



Lorica in lateral aspect hemispherical, somewhat depressed, 

 ventrum flattened ; frontal border somewhat excavate trans- 

 versely, elastic and contractile ; dorsum not crested, but 

 anteriorly flattened, the lateral borders of the lorica being 

 somewhat compressed and slightly concave, the dorsum thus 

 showing on each side a slight posteriorly convergent ridge ; 

 foot single-jointed; toe exceeding the lorica in length, 

 tapering to a finely acuminate termination ; accessory basal 

 stylets small, from four to six in number, voluntarily and 

 separately movable ; dorsal antenna prominent, located on 

 the flattened region about one third the length of the lorica 

 from the frontal border, the setse few (apparently only two), 

 stout and seemingly flesliy ; each lateral antenna at the base 

 and in front of a stout, slightly curved, acuminate thorn-like 

 process ; eye single, red, at the extremity of a saccate lobe of 

 the large brain ; occipital region of the front bearing a con- 

 spicuous subcylindrical proboscis-like organ, which is flexible 

 and movable. 



Length of the lorica, including foot, go^- inch ; height 

 (depth) of lorica 3^-^^- inch ; length of toe j|q inch. 



This form is remarkable for the apparently fleshy setaj of 

 the dorsal antenna and for their fewness ; but it is chiefly 

 notable for the peculiar and characteristic thorn-like processes 

 which accompany and perhaps form a part of the lateral 

 setigerous antennae. The short apically concave antennse are 

 so close to these thorns or so intimately connected with them 

 that they cannot be optically separated. 



The internal structure calls for no special mention. 



Cathypna scutaria, sp. n. (PI. XIV. fig. 7.) 



Lorica broadly elliptical in outline, punctate ; frontal 

 borders excavate, the pectoral more deeply so than the dorsal ; 

 fronto-lateral apices subacute; posterior region much depressed 

 and continued as a conspicuous, somewhat dorsally curved, 

 shield-like projection dorsad to the foot and covering it, the pos- 

 terior border concave, the postero-lateral terminations obtusely 

 pointed ; dorsal antenna single, apparently a small setigerous 



