102 



also in the Hamilton group at Bartlett's Mills, near Arkona, Township of Bosan- 



Branches slender, fifteen 



Colborne ; 

 quet. 



125. RETEPORA PHILLIPSI (Nicholson). 



Retepora Phillipsi (Nicholson), Geological Magazine, April, 1874. 



Polyzoary infundibuliform, or forming a flattened expansion, 

 to eighteen in a quarter of an inch measured transversely, parallel, flexuous, not united by 

 dissepiments, but coalescing at intervals of about a third of a line, and over spaces of the same 

 length. Fenestrules oval, six or seven in the space of a quarter of an inch measured vertically, 

 seven or eight in the same space measured diagonally (five in two lines on an average), regu- 

 larly alternate in contiguous rows. Cells in two alternating rows upon each branch, the rows 

 separated in decorticated specimens by a distinct impressed line. Three cells to the length 

 of a fenestrule, sometimes only two, and one or two opposite the points where the branches 

 coalesce. Reverse unknown. 



This is a genuine Retepora, and is closely allied to the pre- 

 its general form and its biserial cells. It is, however, 

 readily distinguished by the moie slender, crowded, and apparently 

 non-carinate branches, the much smaller size of the fenestrules, 

 and the greater number of these openings in a given space. I have 

 named the species in honour of Professor Phillips, to whom we 

 owe so many descriptions of Devonian and Carboniferous fossils. 

 Locality and Formation. Corniferous Limestone of Port 



ceding in 



Genus CRYPTOPORA (Nicholson). 



FIG. 39. 



a. Fragment of Retepora Phillipsi, 

 (Nich.) natural size ; b, Fragment of 

 the same in which the outer non-cel- 

 luliierous layer has been removed, 

 showing the beaks of the cells, en- 

 larged. From the Corniferous Lime- 

 stone. 



(Canadian Journal, Vol. XIV., No. 2, and Annals of Nat. History, Feb. 1874.) 

 Polyzoary forming a rigid infundibuliform calcareous expansion, springing irorn a strong, 

 solid, branching foot-stalk or rhizome. Exterior of the co3noeciurn, forming a continuous, 

 non-perforated, thin, calcareous membrane, internal to which is a second or intermediate 

 layer, the two being composed of the amalgamated or coalescent branches (" interstices "). 

 This intermediate layer is marked by shallow longitudinal and bifurcating sulci corresponding 

 with the lines between the branches, and its surface exhibits reticulating lines which corres- 

 pond with the bases or proximal ends of the cells. The internal surface of the intermediate 

 layer carries the, cells, which are flask-shaped, and are arranged in double rows, forming 

 regularly flexuous lines, enclosing ovalinterspaces, exactly as in Retepora: The oval interspaces, 

 however, instead of constituting so many " fenestrules," are the bases of so many pillars, which 

 proceed perpendicularly inwards, across a central space, to join with an internal calcareous 

 membrane which forms the innermost lining of the funnel-shaped frond. 



It follows from the above description that the mouths of the cells in Cryptopora, neither 

 open on the exterior of the frond, as is commonly the case in Fenestella, nor open on the 



interior of the polyzoa- 

 ry, as is the case in the 

 mfundibuliforni species 

 of Retepora. On the 

 contrary, we have in 

 this extraordinary gen- 

 us 'the entirely unique 

 arrangement that both 

 the internal and ex- 

 ternal aspects of the 

 funnel-shaped frond are 

 to all appearance closed 



Cryptopora mirabilis (Nicholson). A. A partially decorticated specimen, natural size; J^y a continuous -Calca 

 B. A small portion of the same, showing the inner ends of the perpendicular columns en- , , 



larged ; C. Another partially decorticated specimen, springing from a strong foot-stalk, TCOUS membrane. JLne 

 natural size ; D. Part of the interior surface of the intermediate layer, showing the mouths pp lla nrp no j- 



c Qtirl tVio Vvi*nl.-r itafitAiirlif^iiln *- ^-u-ilnt-i-it-ir- mtln wrs\*l . Z7 A ,-..-.,.-.11 wmw+tnit *-*f fl-ni V>C11O tilt IJwli 



FIG. 40. 



of the cellules and the broken perpendicular columns, enlarged ; E. A small portion of the ^ lla alc uut F laocL * u P n 



frond greatly enlarged, and somewhat diagrarnmatically represented ; F. Transverse section either of the free SUT- 



of part of the frond enlarged, and also represented in a slightly diagrammatic manner ; a. The f f , i 



external membrane ; b. The intermediate sulcated layer ; c. The central space containing the la C6S ( 



cells and traversed by the perpendicular columns ; d. The internal membrane. but OCCUpy 



a central 



