225 
of the corallum Ihe axial fossa does not quite extend to the end 
of the corallum. Gardiner regards this feature as one of the 
chief characteristics separating this species from F. echinata, but this 
is probably due to the flatness of the corallum in the type-specimen. 
Also in flat specimens of F. echinata the axial fossa sometimes 
extends to the anterior and posterior end of the corallum. 
Anaong the material of the Siboga Expedition there is one large 
specimen from Timor, classified by van der Horst with Fungia 
echinata var. parvispina Ddderlein (cf. van der Horst 1921, PI. I, 
fig. 7). This specimen corresponds in every detail with the speci¬ 
mens in my material and has therefore also to be identified with 
Flerpolitha simplex. 
There are also two specimens belonging to H. simplex in the 
collection of the U. S. National Museum in Washington. In one of 
these the axial fossa is divided in seven parts, in the other in 
four parts. Both have very small costal spines. 
In the following table the measurements in mm of all known 
specimens of H. simplex are given: 
Locality 
Greater 
diameter 
Lesser 
diameter 
Height 
Remarks 
Banda 
84 
41 
13 
85 
43 
13 
jy 
89 
43 
15 
119 
52 
22 
Broome, 
Australia 
150 
49 
21 
after Folkeson (1919). 
Banda 
192 
69 
48 
specimen regenerated at both 
extremities. 
205 
73 
45 
specimen regenerated at one 
extremity. 
n 
206 
78 
50 
Tripartite specimen. Breadth 
measured in one radius 
Philippine Islands 
215 
91 
64 
specimen in U. S. Nat. Mus. 
S. Nilandu, 
Maldives 
250 
65 
50 
Type-specimen (cf. Gardiner, 
1905). 
Philippine Islands 
252 
65 
84 
specimen in U. S. Nat. Mus. 
Siboga Expedition, 
Stat. 60. 
312 
100 
53 
Vidensk. Medd. fra Dansk nalurh. Foren. Bd. 79. 
15 
