660 C. H. MARTIN. 
full of difficulties. It has always been assumed that the 
proboscidiform individual represents more closely the an- 
cestral acinetarian form, and that the vermiform individual is 
a more recent development. If this point of view is accepted, 
it is rather remarkable that in the various species of Ophry- 
6a 64 
( ) 
\ E y 
ee 
64 
6a | 6° 
TEXT-FIGURE 6.—Diagrams of the Proboscidiform and Vermi- 
form individuals of Ophryodendron sertularie (A.), 
O. abietinum (B.), O. trinacria (C.), and O. multicapi- 
tatum (D.), to show the similarity of the Vermiform indi- 
viduals and the diversity of the Proboscidiform individuals. 
(2 Searcher, comp. oc. + 4 mm., apochromat.). 
odendron the vermiform individuals are almost indis- 
tinguishable in shape, whereas the proboscidiform individuals 
are absolutely different from one another (text-fig. 6). In 
this case, apparently, the more primitive proboscidiform indi- 
vidual has undergone far more extensive changes than the 
more recently developed vermiform individual. It might be 
suggested that the vermiform individual, once it had been 
