336 Barber . — On Nematophycus S torrid, nov . s/. 
is seen in Fig. 15. The large tube, at this point, appears to 
give rise to branches of nearly the same diameter as the small 
tubes. At a short distance from this point the smaller tubes 
are branching considerably; and, from a careful examination 
of the sections, I find numerous cases of small tubes branching 
in the spaces (Fig. 16). The branches are, however, all uniform 
in size ; and where a large tube divides, its branches have 
much the character of the similar branches of N. Storriei. 
The smaller tubes appear to me to be segmented. All 
search after such dividing walls in the larger tubes has been 
fruitless, and the many delusive appearances, in examining a 
fossil section under high powers, has made it difficult to be 
certain regarding this point. 
I have succeeded, however, in observing appearances in 
isolated tubes which have convinced me that the smaller tubes 
are really divided by transverse walls (Fig. 16). The relation 
of large tubes to small tubes remains a mystery, and the 
introduction of transverse walls into the smaller tubes renders 
the classification of the fossil a matter of difficulty. 
Such are the results of my examination of slides prepared 
from a single specimen forwarded from Canada. An ex- 
haustive study of the numerous slides in Sir William Dawson’s 
collection would be necessary before the correctness of these 
observations could be determined. 
With regard to the function of the radiating spaces of 
N. Logani , I have a certain amount of difficulty in accepting 
Professor Penhallow’s suggestion of ‘ branching depots/ I do 
not think, at any rate from the illustrations appealed to, that 
the connection between large and small tubes has been 
‘ proved 1 .’ I have shown that branching is not confined to 
the spaces in N. Storriei. The following contradictions 
regarding allied forms are to be noted. In N. laxiim, where 
the smaller tubes are excessively numerous, ‘ there are no 
spaces at all/ In N. Storriei , where there is no small-tube 
network, the spaces are particularly numerous and the 
branching well-marked. It appears to me, in consideration 
1 Penhallow, loc. cit., p. 43. 
