BY W. 8. DUN. 437 



almost cei'tain that the County Wellesley beds are of the same 

 age as those whose contents were examined by Mr. Hall. 



In April, 1897, Mr. Carne made a further collection from 

 Stockyard Creek, Parish Alexander, County of Wellesley, and it 

 ■was found that besides the graptolites already recorded — Dicran- 

 ograptns furccrtus, Hall, Diplograptus cf. palmeus, Barr., D. cf. 

 rectangular is, McCoy, Dicellograptus extensus, Hall, D. sp , 

 Olimacograptus sp. — there were four specimens of the bluish slate 

 showing evidence of sponge structure. The skeletons, as is so often 

 the case with Lower Silurian sponge remains, are pyritised, and 

 though little of the detail can be seen it would appear to be a 

 form of Protospongia. No trace of the individual structure of the 

 hexactinellid skeleton spicules can be made out, the body mass 

 being represented by an irregular reticulation of very delicate 

 lines of pyrites, so thin that a lens is useless. The general form 

 of the sponge was probably like that of Protospongia cyathi- 

 Jbrmis, Dawson and Hinde, from the Cambro-Silurian of Little 

 Metis Rivei', Canada.* It is of elongated oval shape, about one 

 and a half inches long as preserved. The regular tetrangular 

 disposition of spicules and their cruciform appearance typical of 

 Protospongice is not seen. At one end, the lower, can be seen 

 the remains of the long, simple anchoring spicules. In one case 

 seven long ones, inserted for a considerable distance into the body 

 mass, ai'e pi-eserved. The top, with the osculum, is not well 

 pi'eserved, so that it is impossible to say whether, as in the case 

 of P. cgathijbrmis, there are any protective spicules present. 



Mr. T. S Hall has already recorded two species of Protospongia, 

 P. reticulata and cruciformis, from Bendigo.f These forms 

 present the typical arrangement of spicules in almost rectangular 

 lattice structure. 



* Ti-aiis. R. Soc. Canada, 1889, vii p. 43, fig. 13. 

 t Proc. R. Soc. Vict., 1889, i. (N.8.), pp. 60-61, PI. 4. 



