112 
Dimensions. — The incomplete specimen before me is only four centi- 
metres long’, but its probable normal length is seven centimetres. The 
diameter of the calice is three and a half centimetres. 
Distinguishing Characteristics. — According to my learned and excel- 
lent friend, Mr. J. Thomson, this species differs from all its known congeners 
hy the form and arrangement of its septa, and also by the quite unique 
arrangement of the vesicles which fill the interseptal loculi. The species 
which it seems most to resemble in its internal structure is Cgathophyllum 
regiimi, J. Phillips ; but as the latter is always compound and astrseiform, it 
cannot be confounded with the former. 
formation and Localities. — I cannot positively assert that this species 
is Carboniferous, althougli all the others from the same locality, Colocolo, do 
belong to that formation. 
Genus — LOPHOPHYLLUM, Milne JEdwards and J. Ilainie. 
1. Lophophyllum minuttjm, L. G. de Koninck. 
PI. V, Pig. 5. 
Corallum rather short, like a small bent horn, with a deep circular 
calice, covered by a thick epitheca, ornamented with closely-packed longi- 
tudinal costm and faint rings of growth. The septa number thirteen,^ two 
extending to the centre of the calice, and serving as a limit to the fossula, in 
the middle of which is another septum only two-thirds the length of the 
adjoining septa. There is no trace of endothecal dissepiments. The colu- 
mella is a little compressed laterally, and slightly eccentric. 
Distinguishing Characteristics. — This species is closely allied to my 
Lop)hophgll'um hreve, having the same number of septa, but differing from it 
by its general shape, which seems to me more slender, and above all by the 
lonf^itiidinal costae of its external surface. In this last characteristic it 
resembles Lophophyllum eruca, McCoy, from which it differs by its two septa 
reaching the centre of the calice, the species described by McCoy having only 
a single septum extending beyond the others and reaching the columella. 
Dimensions. — The diameter of the calice is seven millimetres. I am 
unable to give the other dimensions, owing to the fragmentary state of the 
specimens. 
[Fig. 5a, however show's eighteen sepia. — T.W.E.D.] 
