1921] NATURAL SCIENCES OF PHILADELPHIA. 139 



complete circle to rejoin the base of the cell on the opposite side." 

 In most of the specimens, the capsule is quite colorless, but with 

 age it grows yellow; it is mainly of a cellulose nature, as is easily 

 shoAvn by the chloride of zinc reaction. Iwanoff (19), however, 

 speaks of the violet coloration as only in the shell, the annular ring 

 remaining colorless. Yet I have seen that very ring distinctly 

 colored, and probably Iwanoff's negative results were due to a 

 defective quality of the reagent. 



The protoplast itself, which hardly fills one-half of the capsule, 

 contains a large olive-green or olive-golden chromatophore, in the form 

 of a curved transverse lamina; then very small pure and shining 

 globules, often a large spherule of leucosine, and, in the anterior 

 part, a large vacuole, or sometimes two. Does this vacuole, or 

 one of them, represent here a contractile vesicle? Iwanoff indicated 

 it as such; but in one of the observed individuals I happened to 

 see, at the posterior extremity, a very distinct vacuole suddenly 

 collapsing, just like a normal contractile vesicle, and it may be 

 asked if its true position would not be there, the anterior vacuole 

 being concerned with the capture of food? A nucleus was not 

 seen, being hidden, very likely, in the concavity of the green lamina. 

 Iwanoff, however, mentions the existence of "a small nucleus, some- 

 what above the middle." As to the pseudopodia, which we mast 

 consider somewhat more at length, the spherical protoplast does 

 not reach with its upper extremity so far as the aperture of the 

 shell; it appears, in fact, suspended inside the cavity, and held in 

 place by means of a plasmatic stalk, which arising from the median 

 upper point of the body, goes straight to the mouth of the shell. 

 But there, at the very opening, this stalk abruptly divides into 

 four, five, six, and up to eight lateral threads, which diverge in all di- 

 rections ; they are very thin, smooth and rigid, genuine pseudopodia, in 

 fact, and they behave as such; tiny microbes are caught, slowly ghde 

 towards the mouth of the shell, then reach the central stalk, along 

 which they are seen to descend with a ten-fold rapidity. It often 

 happens, when the fishing district proves rich, that the captured 

 microbes come down in too great numbers, and are then obliged 

 to accumulate, waiting for their turn; it is, indeed, a very interesting 

 sight to notice them swallowed one after another down the main 

 trunk (Plate VII, fig. 49). 



I have never been able, among these rigid pseudopodia, to detect 

 any appearance of a flagellum, nor any transformation of a rigid 

 thread into a swinging one, and my own observations entirely con- 

 firm those of Scherffel (30), when he says: "Then also with Chry- 

 sopyxis animal-like ingestion of food occurs!" and when he adds: 



"^According to Iwanoff (19), the construction of this ring is effected in a very 

 curious manner: the animalcule, in the state of a naked zoospore, turns several 

 times around the Zygnema thread, depositing behind itself a fine train of muci- 

 laginous matter, which soon will harden into a complete ring. 



