SOME OBSERVATIONS ON ACINETARIA. 629 
Some Observations on Acinetaria, 
By 
Cc. H. Martin, B.A., 
Demonstrator in Zoology at Glasgow University. 
With Plate 15, and 6 Text-figures. 
Part 3.—The Dimorphism of Ophryodendron. 
ContTENTS. 
PAGE 
(1) Introduction . : : : 7 029 
(2) Historical : : 3 : . 631 
(3) Material and Methods . : i: 5 (7 
(4) The Structure of the Proboscidiform Individual . 638 
(5) The Structure of the Vermiform Individual . 642 
(6) The Feeding of Ophryodendron, with a Note on 
Nematocysts in some other Protozoa : . 644 
(7) The External Budding of Ophryodendron . . 648 
(8) The Ciliate Embryos. : : . 652 
(9) Conclusions. : ; . 655 
(10) Summary of Results : : . 661 
1. InrRopvucrTION. 
Instances of heteromorphism are fairly common amongst 
Protozoa, especially in the c»se of parasitic forms, but in all 
the known cases, as far as " am aware, where this occurs in 
free living forms, the differences are comparatively slight. 
These differences can often be connected with the Schizo- 
gonous and Amphigonous stages of a complicated life history 
(e. 2. the megalospheeric and microspheeric forms of Forami- 
nifera), whereas in the case of parasites, in which the differ- 
