334 Messrs, Yoiinj!^ on new Carboniferous Polyzoa. 



paper wo sent to Professor Pliillips specimens of ^/i. ^ra«7c, 

 and received in reply the following note, among the last which 

 he wrote : — 



"April 3, 1874. 



" My I)kAR Sir, — I agree witli yon in referring yonr bcau- 

 tifnl specimens to the three species (.lA r/raei/is^ M. rhoinhiferay 

 M. niferj)oj-o.<}a) named in my Ixioks (' Yorkshire,' vol. ii,, and 

 ' ralax>zoic Fossils '). Yonr examples are better than mine 

 were ; bnt I have no donbt of the reference. The axis, which 

 is jointed in yonr specimens, has probably been examined 

 (small as it is) in transverse sections. The difference of oppo- 

 site faces in (J. or Bh. rhomhifera is very interesting 



" Yours truly, 



" John Phillips." 



The appearance of jointing is fallacious, as Prof. Prestvvich 

 may ascertain, the specimens having been retained by Prof. 

 Phillips for the Oxford Museum. 



Rhabdomeson, Young and Young, 1874. 

 Rhabdomeson rhomhiferum, Phillips's species. 



Ceriopora rhomhifera, Phillips. 



Stems slender, cylindrical, free ; branches of nearly equal 

 diameter, given off at wide intervals, as in lih. gracile, and 

 at right angles to the stem. Cells in rpiincunx all round the 

 stem ; they open at the bottom of depressed areas which are 

 rhomboidal or hexagonal in outline and are bounded by narrow 

 tubcrculated ridges, the tubercles on which are larger at the 

 an^'les of junction ; average number of tubercles round each 

 area, sixteen. Here and there depressed pits with quadran- 

 gular boundaries intervene between adjacent cell-areas ; but 

 they are cffical, and do not show in transverse sections. Cell- 

 areas more numerous on one face than on the other, in the pro- 

 portion of 2 to 3, the size of the areas being inverse to their 

 number. Central axis slender, slightly flexuous, and without 

 transverse septa. Cells conical, tapering interiorly ; their 

 casts identical in form with those of Rli. gracile (Ann. & Mag. 

 Nat. Hist. 1874, xiii. pi. xvi. b. figs. 3 & 4). 



Locality. — Hairmyres, East Kilbride, in limestone shales, 

 and sparingly in cvciy bed which jdelds Rh. gracile. 



This species is easily distinguished from Rh. gracile : 1, its 

 stem is only half the thickness ; 2, the cell-areas are larger 

 and angular ; 3, the prominent angular tubercle is wanting ; 



