1870.] { Porcupine' -Expedition Madrcporaria. 293 



and a small Lsis. Tlie species is hitherto unknown except in the Sicilian 

 miocene*. 



Flabellum laciniatum, Ed. & H. — This is the TJlocyathus arcticus of the 

 late Prof. Sars. Many specimens were dredged up ; but most of them were 

 broken, in consequence of the extreme fragility and delicacy of the theca. 

 There are no pali ; therefore Sars's terminology is not in accordance with the 

 received system. The form was familiar to me from Seguenza's drawing 

 of a dilapidated Flabellum (which is always found broken*) ; and it is now 

 evident that TJlocyathus must give place to Flabellum. The species links 

 Flabellum to Desmojihyllum : it is not known in the recent Mediterranean 

 fauna. 



Lophohelia prolifera, Pallas, sp., is apparently a common coral in the 

 north-western British seas. 



Temperature. 



o 



It was dredged up in No. 5 at a depth of .364 fathoms . . 48*8 



13 „ 208 „ .. 49-6 



14 „ 173 „ .. 49-6 



15 „ 422 „ .. 47-0 

 25 „ 164 „ .. 46-e 

 54 „ 363 „ 31*5 



and also at a depth of from 350 to 600 fathoms in the cold area to the 

 north-west. 



All the specimens show great density of the calcareous skeleton ; and 

 active nutrition may be inferred on account of the repeated gemmation, the 

 large size of the calices, and the numerical development of the septa. Great 

 variability occurs in the coralliles forming a stem ; and the shape of the 

 calices is very diverse. 



It is very interesting to find some specimens hearing elongate and 

 more or less claviform corallites with the peculiar gemmation of Lophohelia 

 anthophyllites, Ellis and Solander, on some portions of their stem, and the 

 usual-shaped corallites of Lophohelia prolifera on others. 



A separate corallum, which must he referred to Lophohelia antho- 

 phyllites, Ellis and Solander, was dredged up at No. 54. 



The variation of the gemmules of several specimens is sufficiently great 

 to absorb Lophohelia subcostata, Ed. & Haime ; for fragments of the 

 corallum of Lophohelia prolifera exist which possess all its so-callec 3 

 specific peculiarities. 



A careful examination of Lophohelia Defrancei, Defrance, sp., from the 

 Messinese Pliocene and Miocene deposits, and a comparison of its struc- 

 ture with the numerous specimens dredged up in the ' Porcupine ' Expedi- 

 tion, lead me to believe that it is identical with Lophohelia prolifera. 



* Ssguenza, "Disquisiz. Paleont. int. ai Corall. Foss.," Mem. della Reale Accud. 

 dell. Sci. Torino, serie ii. tomo xxi. 1864. 



