124 PROCEEDINGS OF THE ACADEMY OF [PaRT I 



in Craspedomonads, but instead, there is a thick layer of deUcate 

 purely ectoplasmic substance, which constitutes, in fact, the ma- 

 terial for the building up of the collar. After a moment's observa- 

 tion, one notices the protoplasmic layer growing upwards, becoming 

 cup-shaped and more and more lengthened, and at last it has grown 

 into a funnel, whose length nearly equals that of the animalcule 

 itself, but it is so thin and delicate that only the two borders, right 

 and left, can be seen, and as for the anterior rim it remains (as in 

 most of the Craspedomonadina) entirely invisible. 



In Salpingoeca -polygonatum, as well as in several other rep- 

 resentatives of the group, one might easily believe in the presence 

 of two concentric protoplasmic collars; but it would be a mistake, 

 and I can only agree with the conclusions of Lemmermann (24: 

 p. 564) relative to Diplosigopsis frequentissima: "As there is, in 

 fact, in that species but one plasmatic collar, it must pass to the 

 genns Salpingoeca." But when the same observer continues- "How 

 it is with the other Craspedomonads where two plasmatic collars 

 have been mentioned, remains to be investigated," I should go 

 further yet and should not be astonished if both the genera Diplosiga 

 and Diplosigopsis had to be abandoned. 



The flagellum, about IJ^ times as long as the animalecule, is rather 

 thick and distinct, and points straight upward, swinging with longi- 

 tudinal undulations that sometimes affect the whole length of the 

 flagellum, and at other times only concern the tip. 



I very often had the opportunity to observe the reproductive 

 phenomena, which are very interesting here. In Craspedomonads, 

 transverse division, quite an exceptional fact among Flagellata, has 

 been several times mentioned, and S. Kent, for instance, figures it 

 in Salpingoeca gracilis, on Plate VI of his great classical work. 

 Within the capsule are seen the two products of the division, still 

 united to each other by a very thin tubular film, which soon will 

 cut in the middle and form the two new collars. My own observa- 

 tions quite confirm the facts; first the body retracts, then loses its 

 shape and appears an ovoid mass, and finally this mass becomes 

 transversally sectioned ; the upper of the two animalcules thus formed 

 then rapidly rises towards the aperture of the shell, drawing out 

 at the same time an axial, varicose filament or future flagellum, 

 which gets thinner and thinner, and forming also around the cir- 

 cumference a thin tubular protoplasmic film, which unites the two 

 new individuals (Plate VI, fig. 21). Each of these then lengthens., 

 and the upper one becomes somewhat curved, leans with its con- 

 cave side against the border of the capsule, and disengages its fla- 



