1886.] 



MICROSCOPICAL JOURNAL. 



227 



Probably its favorite habitat is on the 

 radicles of the lesser duck - ^veed 

 {Lemna minor) . I have also found 

 it quite often on Vaucheria^ and oc- 

 casionally on other algse. It is dis- 

 tinctly visible to the unaided eye, and 

 after having once been pointed out 

 it M'ill ever afterwards be easily rec- 

 ognized. I have only succeeded in 

 finding two species in California, 

 H. viridis and H. vulgaris^ and 

 these appear absolutely identical with 

 those species as found in the Eastern 

 States and in Europe. Mr. King, of 

 Santa Rosa, reports having found 

 H. fusca recently in Mark West 

 creek. 



The little ' plant animal ' which we 

 have been considering to-night has 

 been a celebrity in the scientific world 

 for nearly a century and a half. Nor 

 is this to be wondered at, for in the 

 whole range of microscopic life there 

 are few, if any, animals possessing 

 equally attractive features to the in- 

 vestigator. Its graceful movements 

 and interesting food-habits, its com- 

 paratively simple strvicture, its plant- 

 like appearance, its wonderful meth- 

 ods of reproduction, and the impor- 

 tant light which many facts in its his- 

 tology have thrown upon the elucida- 

 tion of structure in the higher ani- 

 mals, all invite attention and study. 

 Nowhere is more strongly illustrated 

 the practically inexhaustible nature 

 of microscopical research, for, not- 

 withstanding the fact that Hydra has 

 been the subject of continued obser- 

 vation since the days of Leenwenhoek 

 and Trembley, yet even its latest in- 

 vestigators, while adding to our 

 knowledge, have also opened up a 

 new series of questions calling for 

 additional patient search, improved 

 methods of study, and increased opti- 

 cal facilities. We may rest assured, 

 therefore, that although Hydra was 

 one of the very first ' revelations 

 of the microscope,' it will never- 

 theless be profitably studied as long 

 as that magic lens has a single 

 devotee. 



New Members of the Infusorial 



Order Choano-Flagellata. 



S. K.— IT. 



BY DR. ALFRED C. STOKES. 



]\Io7iosiga llmjiobla, sp. nov. — 

 Fig. I. 



Body broadly obovate or top shaped, 

 somewhat changeable in form, longer 

 than wide, tapering posteriorly to the 

 pedicle; flagellum long; pedicle three 

 to four times the length of the body ; 

 contractile vesicles, two, oppositely 

 situated near the centre of the lateral 

 borders. Length of body 03V0 inch. 

 Habitat. — Pond water. Solitary. 



This form, aside from its distinctive 

 shape, may be readily recognized by 

 the unusual equatorial position of the 

 contractile vesicles, these being com- 

 monly located near to the posterior 

 extremity. 



In respect to its habitat it seems 

 somewhat careless. It was first ob- 

 tained from pond water that, with 

 Proserpinaca and other aquatic 

 plants, had been standing for several 

 months in an aquarium ; it was again 

 taken from the fresh waters of a deep 

 pond in early spring, and again on 

 Utricularia from the cedar swamps 

 of the New Jersey pine barrens. In 

 all these localities it retained its chai-- 

 acteristic form, its solitary life, and the 

 distinctive position of the contractile 

 vesicles. The rich color of the cedar- 

 swamp water had not altered the pe- 

 culiar pale-green tint so noticeable in 

 the endoplasm of Monosiga as well as 

 in the members of the allied genera. 

 Salpingoeca eurystoma^ sp. nov. 

 Fig. 2. 



Lorica vase-shaped, about one and 

 one-half times as long-as broad, some- 

 what inflated centrally, thence taper- 

 ing posteriorly to the pedicle ; ante- 

 riorly constricted, and thence rapidly 

 expanding to the aperture, which 

 forms the widest part, its margins 

 strongly and conspicuously everted ; 

 pedicle subequal to the lorica in 

 length; enclosed animalcule ovate or 

 sub-pyriform, occasionally connected 

 with the lorica by a fine posteriorly 



