472 JOHNSON. [ Vol. V 1 1 1 . 



species, it must be remembered that all the specimens came 

 from a single locality ; and I have found that Stentors, like 

 many other animals of wide distribution, offer strongly-marked 

 local varieties. 



I . St cut or igneiis, Ehrbg. 



This species was found in abundance in two small ponds in 

 Falmouth, Mass., during the summer of 1891. One of these 

 ponds — a mere pool covering the bottom of a "kettle-hole " — 

 is located near the village of Wood's Holl. The pond is very 

 shallow and choked with Sphagnum, among the fronds of 

 which the Stentors live. The other pond was much larger, 

 situated two miles from the first, near the village of Ouisset. 

 Here the Stentors were found among pond-lilies {Nyviphcea 

 odorata and Brasenia peltata) and other water-plants. They 

 were not uniformly distributed, but colonized in certain places, 

 apparently limited to the south side of the pond. This 

 was probably owing to the fact that the other shores were 

 wooded, and consequently shaded during a part of the day ; for 

 5. igneus, like all chlorophyll-bearing Stentors, is heliotropic. 



This form agrees very accurately with Stein's description 

 and figures of ^. igneus, and I have no hesitation in referring it 

 to that species. The shape assumed by the animal in swim- 

 ming varies from conical to pyriform. When attached and 

 extended it assumes a trumpet-form very nearly like that of 

 5. polymorpJms, but not so attenuated. I have always found 

 symbiotic green algae (ZoocJilorclld) present. The red pigment, 

 however, is most frequently wanting. I have never found it in 

 sufficient quantity to give a red tint to the animal as seen with 

 the naked eye. The scantiness and frequent absence of 

 pigment may be only a local or seasonal peculiarity, inasmuch 

 as Leidy ('80) described a Stentor ^ from New Jersey in which 

 the abundant pigment-granules imparted a crimson or lilac 

 color to the animal. 



As is well known, the meganucleus of 6". igneus is a spherical 

 or oval body, either single or multiple. Only small individuals, 



1 S. atnethystinus, Leidy. T find nothing in liis description, however, that would 

 separate this form specifically from .S". igneus. 



