INVERTEBRATE ANIMALS. 1 565 



been placed in the recent genus Leucandra, Haeckel. The largest of 

 these fossil sponges is under 4 mm., or about one-sixth of an inch in 

 height, and the spicules in their walls are as perfect as in recent 

 specimens. A remarkable assemblage of small Calcisponges has 

 also been discovered by Mr Walford in the Inferior Oolite (zone of 

 Ammonites JParkinsoni) of Dorset. In their diminutive proportions 

 they resemble living Calcisponges, but they all possess a structure of 

 solid fibres, characteristic of Pharetrones. They mostly belong to 

 the genera Eudea, Perofiella, Blasti'nia, and to a new genus not yet 

 described. Calcisponges of larger dimensions, belonging to Peron- 

 ella and Ly??inorea, are also abundant in the Inferior Oolite of 

 Cheltenham. Certain zones of the Great Oolite in the neighbour- 

 hood of Bath are very rich in Calcisponges, principally of the genus 

 Peronella. Higher up in the Oolitic series there is a well-marked 

 zone of Calcisponges in the Lower Coral Rag of Yorkshire. They 

 have mostly been hitherto placed in Stellispongia ; species of Per- 

 onella and Blastinia are also present." 



Stromatoporoidea (p. 229). 



Since the earlier portion of the present work was written, the 

 author has had the opportunity of studying the fasciculus of Dr 

 Waagen's Monograph on the " Salt Range Fossils," which deals 

 with the Hydrozoa (' Palseontologia Indica,' Ser. XII., No. 7, 1877). 

 The most important point brought out in this memoir is, that the 

 " Productus Limestone " of the Salt Range of India, the age of 

 which is Permo-Carboniferous, contains various Hydrozoa which 

 are more or less closely related to Stromatopora proper. For these 

 the new genera Disjectopora, Circopora, Carterina, and Irregulato- 

 pora are proposed ; but it would be impossible to make the struc- 

 ture of these intelligible without illustrations. It may, however, be 

 considered as proved that the geological range of the Stromato- 

 poroids, as a group, has by these researches been extended into the 

 beginning of the Permian period ; the latest undoubted types of the 

 group previously known being Upper Devonian. 



Dr Waagen, further, deals at some length with the general struc- 

 ture and zoological affinities of the Stromatoporoids. He divides 

 them into two families, and refers them to the Hydro cor allince. It 

 is unnecessary, however, to discuss Dr Waagen's views on these 

 subjects here ; since the conclusions which he has reached would 

 probably have been more or less modified had he been acquainted 

 with the previously published " Monograph on the British Stromato- 

 poroids" (Palaeontographical Society, 1885) by the present writer, 

 in the general introduction to which the same questions have been 

 dealt with in considerable detail. 



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