121 



to exclud from this species other specimens wliicli "form flattened or sub- 

 hemisphaerical expansions, having their under surface covered by a wrinkled 

 epitheca, attached to some foreign object by a pedunculate base, Jiaving the 

 calices confined to the upper surface only, and not exhibiting any composition 

 of the corallum out of concentric layers." Fkech, on the other hand, stated 

 that the corallum of this species forms lenticular or irregular masses, com- 

 posed of concentric layers. 



Frkch distinguished var. viino)' of this species ; this variety is charac- 

 terized by being composed of much smaller corallites ; the corallites 

 of the type-form measure 1-1.25 mm. along the longer diameter, and 

 •0.75 mm. alo g the shorter; while those of var. minor are only a half or 

 one-third as large as the former. Further the mural pores are said to be 

 numerous in the varietal form, though they are seldom present in the type 

 form. 



The figured specimen from China forms a colony of flattened expansion, 

 apparently composed of a few concentric layers, and^provided wfth calices re- 

 stricted to the upper, somewhat concave, side only. The calices are very ob- 

 lique; the corallites are depressed trigonal, attaining 0.36 mm. along the longer 

 diameter and 0.15 mm. along the shorter; the calices are almost free from 

 septa, provided with a few mural pores and numerous straight, complete 

 tablae, and surrounded by the wall which is never much thickened. Hence 

 it is essentially a small-celled A. siiborbiciilaris, and is provisionally referred 

 to var. minor Frech, although distinguished from the latter by having less 

 .numerous mural pores. 



Locality: — Neighbourhood of Hung-kuo-chi,Ta-kuang-ting,Chao-tung-fu, 

 prov. Yun-nan ; found together with Cylindropliylluni simplex Yabe and 

 Hayas.aka. 



Geological horizon : — Devonian. 



Alveolites siiborbicularis is known from the Middle Devonian of England, 

 Devonian of France, Belgium, Spain, Germany, Poland, Central Russia, 



■Urals, Petshora-Land, Transcaucasia, Altai, western and northern Siberia, 

 northern Shan States, and Tchao-kwa, prov. Yun-nan. The same, or 



■A closely allied species is also known from the Devonian of North 



