248 



HARD WICKE 'S S CIENCE - G O SSI P. 



gregated, adherent, and forming compound animals.* 

 The class was divided into five orders ; but under 

 one order, those of Polypi vaginati, Spongta, Coral- 

 Una, Gorgon/a, and Retepora found a home. With 

 these were associated many of the corals, polyzoa, 

 and anthozoa, which have been separated by later 

 investigators, and placed under classifications alto- 

 gether different from either that of Brown or 

 Cuvier. 



The generic character of Lamarck's Retepora is as 

 follows : Stony, and interiorly porous, with thin, 

 depressed, branched expansions, sometimes free, at 

 others formed like net-work ; the polypiferous cells 

 on one side only, at the upper or internal surface of 



Fig. io2. Fenestella flebcia (McCoy), Hairmyres (Scot). 

 Showing the growth of the dissepiments (a) from the 

 Zooecia ; sometimes from the base, at other times from just 

 below the orifice of the cell. Natural size: about $ih of 

 an inch to two fenestrules. Diastopora megastotna was 

 parasitic upon this. (Transparent.) 



the mass ; and Brown gives as a type of the genus — 

 Retepora eellnlosa, with this restricted specific cha- 

 racter : — Flattened, thin, greatly undulated, with 

 elliptical cells ; inhabits the Indian Ocean. With this 

 before them, I can easily understand howdifficultwould 

 be the labours of the earlier paleontologists. Both 

 Goldfuss's and Phillips's Carboniferous, Devonian, 



* Brown's " Zoologist's Text-book." 



and Silurian Polyzoa had to be classified as they were, 

 or remain unclassified, and consequently undescribed. 

 The few fossils at their disposal forced them to be 

 particular with the minute specimens in their posses- 

 sion, and the diagnosis of their species suffered in 

 consequence of their poverty. 



From the time when Phillips wrote his ' ' Geology 

 of Yorkshire," till the time of William Lonsdale, the 

 founder of the "Devonian System" in geology, 

 very little labour was bestowed upon the Palaeozoic 

 Polyzoa. Like the rest of the investigators, he was 

 inclined to place the Fenestella with the Retepora ; but 

 previous to the publication of Phillips's " Palceozoic 

 Fossils of Cornwall, Devon, and West Somersetshire," 

 Mr. Miller, of Bristol, in correspondence with 

 Phillips on Fossil Zoophyta, suggested that a new 

 genus should be constituted for some of the reticu- 

 lated corals allied to Retepora in the Carboniferous 



Fig. 203. Branch of Fenestella with "organisms " like 

 Palieocoryiie " parasitically " attached. 



'■■ftp?-- "-<7**^,V-^.*>'C N 



Fig. 204. This sketch of the fig of F. banyana was in all 

 probability a recumbent form. The figure represents a 

 cavity in the limestone, and shows the processes extending 

 from the frond. — Mr. John Young, F.G.S. Fig. 4, 

 plate 18, "Transactions of the Acad. Sci. St. Louis," 

 vol. i. p. 450. 



limestone. On mentioning this to Mr. Lonsdale, he 

 at once adopted the suggestion, and named a species 

 of the Silurian strata Fenestella Milleri (Lonsd.).* In 

 1 841 Phillips himself adopted this term. 



This more expressive generic term has since been 

 adopted by nearly all writers on Palceozoic Polyzoa ; 

 and Lonsdale gave as a description of the genus, 

 characters altogether different from Retepora, and 

 more in accordance with known facts. It is impos- 

 sible for me to give the exact description as given by 



* Phillips's " Palaeozoic Fossils of Cornwall, &C." Through 

 the kindness of Mr. Plant, curator and librarian of the Peel 

 Park Museum, Manchester, I have been allowed to extract 

 whatever I required, and trace the original figures of specimens 

 from this rare volume. 



