WILMORE : THORXTOX, MARTON AND BROUGHTON-IN-CRAVEN. 369 
2 millimetres, and they are about that distance apart. The 
connecting tubes are not very numerous.* 
Zayhrentis Omaliusi (Ed. and H.). Mr. Carruthers has de- 
scribed two varieties of this species, var. amhigua and var. densa 
(Plate XLVIII.). The latter he recorded from Thornton Quarry, 
and from otlier quarries outside this immediate district. Further 
search has revealed these varieties in Rain Hall, Gill Rock, 
Gledstone Kennels, Marton School, and Clint's Delf Quarries. 
Fine specimens of amhigua are found in Rain Hall ; densa seems 
to occur everywhere. Mr. Carruthers has recognised a new 
variety in some material from Marton School ; this is as yet un- 
named. As mentioned in the earlier part of the paper, this 
species swarms in Thornton Quarry and I have handled hundreds 
of specimens. I have had a great many cut down, and Dr. 
Vaughan and Mr. Ca,rruthers have kindly examined some for 
me. From the examination of a great number, and assisted by 
the notes supplied by the above-named experts, I sliould say 
that the variety densa is much more common than the normal 
type, and that amhigua is not nearly so common. There are 
gradational forms, as mentioned by Mr. Carruthers,t and 
these occur in plenty. Densiphyllid forms of var. densa are 
common. 
Caninia cornucopias (Michelin) occurs - in several exposures, 
and a remarkable feature is the occurrence of the true species, 
as well as the mutation d. 
A new species of Caninia, not yet described, was found in 
Marton School Quarry. 
Cyathaxonia Rushiana (Vaughan) (Plate XLIX., Fig. 1) is 
quite common, especially in the Marton beds. The small septal 
protuberances described by Dr. VaughanJ are noticeable. 
A Cyathaxonia from Marton School is probably a new species, 
but more material must be found before description is possible. 
* I have examined a great many specimens of reticulate and geni- 
culate Syringopora and I find that the number of connecting tubes is 
a very variable character. Milne Edwards and Hanne lay stress on this 
character in the discrimination of reticulata and geniculata. 
t See Bibliographj^, p. 371. Carruthers. 
: Q.J.G.S., Vol. LXIV., p. 460. 
