210 
ampullae are short and pale. The calcareous ring thick and robust 
and in structure very like that of the Hawaiian form. One long 
Polian vesicle and one madreporic canal. — A tuft of gonads on 
the left side and well developed Cuvierian organs. All internal 
organs are of a very pale colour. The deposits in skin are never to 
be mistaken as they are quite different from the above mentioned 
species. The tables have many holes in the disk and the margin 
is smooth; the buttons are 
3—4 times larger than in the 
other species (Fig. 8). In his 
„Notes on the Holothurioidea 
of the Indian Ocean“. II. 
(Spolia Zeylanica IX. 1914. 
p. 176) I. Pearson mentions 
a specimen of M. (Argiodia) 
flavo-casianea from the Red 
Sea. In a letter to Dr. Mor¬ 
tensen he gives the inform¬ 
ation that on further examin- 
ation he has found the spec¬ 
imen to be not an Actinopyga 
(Argiodia) flavo-castanea, but an Argiodia maculata (Brandt). 
Actinopyga aegyptiana Helfer is especially characterized by its 
tentacles which are very siender (Fig. 9), quite pale and nearly 
without disk, while the Hawaiian form has broad, robust, dark- 
coloured disks. The specimen I have had the occasion to examine 
is 4 cm in length, with well developed genital organs of a pecul- 
iar green colour on the left side of the mesentery. The ring is low 
and fine and the single pieces are hard. The ampullae are short, 
pale in colour. 2 Polian vesicles and 1 madreporic canal are pres¬ 
ent. Also Cuvierian organs. The colour of the animal is pale 
whitish with brown spots on the dorsal side. A very prominent, 
white tentacle collar is present. 
The buttons are very similar to those in the Hawaiian form, 
but the tables are much more uneven in the margin (Fig. 10). 
1 have not succeeded in finding buttons of the form which 
Hel fer figures, but I have happened to see similar buttons with 
toothed margin in a preparation where the isolated spicules were 
Fig. 8. Calcareous spicules of A. flavo- 
castanea Tliéel. 170 /i. 
