78 EEPOET — 1880. 



Ptilodicta Meeki, Nicholson, Devonian species/ as well as all the known 

 species of Sulcoretepora of the Garb. Limest. series. 



The Millepora of Lamarck seems to have been the generic type of both 

 Goldfuss and Phillips, and in describing the Carboniferous species, the 

 latter author adopted the class Polyparia of the Radiate Division of the 

 Animal kingdom at that time current among naturalists. It was 

 Phillips' misfortune, rather than his fault, that he had to follow in his 

 classification the authority of those who preceded him. Of the six 

 species of Millepora described, four are easily identified ; the other two 

 are not so easily recognised. 



Millepora rhombifera, PhilL, Geo of Yorkshire. 



„ interporosa ,, „ „ 



„ spicularis ,, „ „ 



„ oculata „ „ „ 



„ gracilis ,, Palaeozoic For. of Devon, &c. 



„ similis „ ,, „ „ Torquay. 



„ verriicosa, Goldfuss. Of this Phillips say, ' a species 

 like this appears at Florence Court, Ireland.' ^ 



No group of Polyzoa, recent or fossil,^ has caused so much trouble 

 to Palaeontologists as the little group here tabulated from Phillips. Mem- 

 bers of it have been referred to no fewer than five distinct genera, and 

 even now they may be safely referred to three, if not to four. Rather 

 than postpone the analysis of the species, I shall prefer to draw upon 

 later work and do it here instead of elsewhere. 



Millepora gracilis is referred to by Phillips in his later work,* for he 

 seems not to have noticed it in the limestone, Toredale limest., or shales of 

 Yorkshire ; yet it is most common from everywhere, whilst the M. rhom- 

 bifera is by far the rarer species. We have the authority of Phillips 

 himself, that the species I am dealing with, were his; for in a letter ^ 

 which he addressed to the Messrs. Young of Glasgow, he says, ' I agree 

 with you in referring your beautiful specimens to the three species (M. 

 gracilis, M. rhombifera, and M. interporosa) named in my books ('• York- 

 shire," vol. ii. and " Palseozoic Fos."). Your examples are better than 

 mine were ; but I have no doubt of the reference, &c.' Morris places the 

 whole of Phillips' species — with the exception of M. spicularis and M. 

 oculata — with the Geriopora,^ the exceptions, for what reason I cannot 

 explain, he places with the Pustulopera of Blainville, a genus that had no 

 existence in the Palaeozoic seas. 



Millepora rhombifera, PhilL, Geo. Yorkshire. 

 „ . gracilis „ Palaeozoic Fos. 



Both Ceriopera, Morris Catalogue. 

 Rhabdomeson gracile and B. rhombiferum. Young & Young. 



Gen. Ch. B. gracile. — ' Stem slender, cylindrical, branching at right 

 angles to the stem and never less than an inch apart ; and consists of a 

 hollow axis formed by a thin calcareous tube, and of a series of cells ranged 

 round the axis . . . apertures of cells, oval . . . ridges tuberculated.' '' 



B. rhombiferum.- — ' Stems slender, cylindrical, free ; branches of nearly 



" Geo. Mag., 1875, pp. 19-20, pi. 6, fig. U. " Geo. of Yorhshirc. 



^ Excepting the Lepralia. 



* Palceozoic Fog. of Cornrvall, Beron Sfc, 1841. 



'- April 3, 1874 ; Aim. 3Iag. of Nat. Hist., May, 1875. 



* Catalogue of Bntish Fossils, 1854. 



' Messrs. Young, Ann. Mag, of Nat. Hist., May, 1874. 



