268 PERCY SLADEN TRUST BPXPEDITION. 
apparent that it is usual for only one species of a Group to be found in any geographical 
region. There are three exceptions to this, but the fact is only the more striking when these 
are critically examined. Thus in the Seychelles region there is F. fungites and madagas- 
carensis, the former a well-authenticated species, but the latter founded on a single 
distorted specimen. From Chagos there is /’. concinna and fieldi, the latter described 
from three specimens. From Hawaii there is /. scutaria,a very well-known species, and 
F. oahensis described from two specimens, the identification of F. pawmotensis having, as 
Quelch (oc. cit. p. 137) admits, to be received with “extreme doubt.” This distribution 
undoubtedly lends support to Déderlein’s grouping of the species. Ifthe species may be 
taken as moderately accurate, it points out in a peculiarly striking manner how in the 
struggle for existence only widely-separated forms, presumably suited to somewhat different 
modes of life, have managed to survive in each region. At the same time it gives food 
for thought as to whether in each of Déderlein’s Groups we are not really dealing 
with separate species rather than with groups of species. 
The following is a list of the specimens examined, representatives of which will be 
found in the Cambridge University Zoological Museum. 
a. Diaseris-group. 
1. Fungia distorta, Michelin. 
Déderlein, Senckenb. naturfors. Gesellsch. Abhandl. xxvii. p. 74, tt. ili., v., figs. 3, 3.4. 
Diaseris distorta, Gardiner, Fauna and Geogr. Maldives & Laccadives, p. 74, t. iii. p. 945. 
Two small specimens of the Diaseris-form, each consisting of about half a disc, the 
one unbroken at its edge but the other divided into six lobes. 
Locality. Cargados Carajos, B7, 45 fms. Previously known from the Red Sea (on 
surface bank), Zanzibar (depth ?), Maldives (22-42 fms.), Ceylon (‘‘ deep water ’’), Chima 
Sea (28 and 43 fms.), and Philippines (6-10 fms.). 
In addition Déderlein identifies a Cycloseris-form from Aldabra, three specimens. 
2. Fungia fragilis (Alcock). 
Diaseris fragilis, Alcock, Journ. Asiatic Soc. Bengal, lxii. pt. 2, no. 2, p. 148, pl. 5. fig. 11. 
Fungia fragilis, Vaughan, U.S, Nat. Mus. Bull. 59, p. 180, pl. 28. figs. 1, la. 
There are two sections of the Diaseris-form which appear to me to belong to this 
species, which scarcely seems to be the same as F. patella, with which Déderlein has 
placed it. 
Locality. Seychelles, F 5, 44 fms. Previously known from Hawaii (43-46 fms.) and 
the Andaman Islands. 
