HYDROCORALLINE GENUS ERRINA, 881 



As regards the distribution it may be said that all the species 

 are inhabitants of deep water (i. e. 50-600 fathoms). Being 

 deep-sea species they are probably widely distributed, but at 

 present E. pourtalesii, E. rarnosa, and E. horrida have only been 

 found in the Pacific Ocean and Malay Archipelago, and the 

 remaining species in the Atlantic Ocean. 



Sjnnipora group of species. 



Coenosteum hard and compact, perforated at the surface by 

 well-defined ccenosteal pores usually arranged in shallow branching 

 grooves iri-egularly an'anged on the surface. Gasteropores 

 without a scale. Dactylopores of two kinds. The larger kind 

 being guarded by long grooved spines (narial processes) crowded 

 and overlapping on the terminal branches, often worn down 

 short and separated by considerable intervals on the stems and 

 older branches (PL XCV. fig. 8). All the grooves of these 

 spines turned towards the apex of the branch. Smaller dactylo- 

 pores not protected by grooved spines, but scattered between and 

 on the projections that guard the larger dactylopores. 



The /Sjnnijwra group is represented by only one species, 

 Errina (aS'.) echinata Moseley, and this species has been found oS 

 Rio de la Plata in 600 fathoms by the ' Challenger ' Expedition, 

 and off Providence Island in the Indian Ocean in 75 fathoms by 

 Professor Stanley Gardiner (4). 



Labiopora group of species. 



Ccenosteum granular and minutely reticulate, without clearly 

 defined coenosteal pores. Gasteropores without scales but some- 

 times protected by short grooved projections or " lips." Dactylo- 

 pores protected by grooved spines of variable lengths, the grooves 

 turned away from the apex of the branch or irregulai'ly in all 

 directions. Some of the dactylopores usually without grooved 

 spines. 



The species of this group that have been described already 

 are Errina aspera Gray, Errina {Lahiopora) antarctica Gi'ay, 

 Ei-rina (L.) moseleyi Ridley, and Errina gracilis von Maren- 

 zeller. 



Errina aspera Avas the name given by Gray to the Linneaii 

 species Millepora asjyera from the Mediteranean Sea. Errina (L.) 

 antai'ctica was originally described by Gi'ay as a Polyzoon 

 {Forella antarctica), but was subsequently redesci-ibed and figured 

 by Moseley as the type species of Labiopora,. The type specimen 

 was found ofi" the East coast of Tierra del Fuego, but a second 

 specimen was discovered by the ' Alert ' Expedition in 30 fathoms 

 ofi^ S.W. Chili and described by Ridley (10). Erina (Z.) mose- 

 leyi was found by the ' Alert ' Expedition oft' the same cosat in 

 2—10 fathoms. Errina gracilis was found oft' the pack ice in the 

 Antarctic Ocean in deep water (von Mai-enzeller) (6). 



1 have had an opportunity of carefully examining a piece of 



