386 TRANSACTIONS OF THE CANADIAN INSTITUTE. [Vou. VIII. 
sionally found entire. Forms like Fig. 6 of Plate XXIV of Mrs. Bury’s 
work are also numerous, and all these when broken up, as they generally 
are, furnish numerous spicules. Asa rule these spines are much larger 
than and often several times the length of the diameter of the more or 
less spheroidal central skeleton of the radiolarian. The larger radiolaria 
are on account of their brittleness very difficult to secure entire, but I 
have managed to isolate a few with very long spines usually of the forms 
figured by Ehrenberg (Barbados Polycistenen Mergel, 1875, Taf. I). 
The largest radiolarian is like a miniature Ordudzna with short spines 
protruding from it at rather distant intervals. Its size is about o'4 mm. 
in diameter. It may be called Ha/zoma, but those who like can have their 
choice of any of the numerous names given to this and similar forms 
with other generic epithets. Nearly all, perhaps quite all, of the jamaican 
forms are really identical with barbadian ones, but few are exactly alike, 
and there is a splendid opportunity here for anyone who wants to make 
species and genera to “create” a lot of them. For my part I consider 
them all referable to the species of which I give a list below, and to 
extend this list is like arranging the leaves of trees into genera and 
species. As Mivart truly remarks the forms of these organisms are not 
evolved by natural or sexual selection, nor indeed do I think those of 
foraminifera are so, though the species of foraminifera when worked out 
by an impartial and discriminating observer are as true and as fixed as 
any other species of animals. Some of them are extremely variable, but 
so are many animals and plants. 
Gregory (l.c. page 295) has given a list of the radiolaria from the Cuban 
marls. As Iam unable to appreciate the specific differences between 
these forms, I could not allege that they are the same as the Jamaican 
ones, but I presume they are, as they are identified with Barbadian forms. 
List of the Jamaican Radtolarta. 
Species 1. LITHOCAMPE Ehrenberg—Barbados Polycistenen Mergel, 
1375; Wat: IN, Bigs 2-2. 
A large number of Ehrenberg’s genera and species belong to 
this specific tvpe, including Lithornithium, and probably 
the whole of Eucyrtidina. 
Species 2. DicTyospiris Ehrenberg. Ibid. Taf. XIX, Fig. 6-13. 
With this goes probably the whole of the Spyridina. The 
development of the spines is mostly individual. 
Species 3. PERICHLAMYDIUM Ehrenberg. Ibid. Taf. XXII, Fig. 12. 
With this goes Calodictya generally. 
