BAHAMA MEDUSA. 
21 
The species of Olindiadie are few in number but are widely scattered. 
Nevertheless the geoiirapliical ran^e of each species is remarkably restricted. 
It seems probable, therefore, that the^^ belong to an ancient race that has 
suffered extinction in the greater part of the world. 
They exhibit relationships both to tli(» Eucoi)id;e and Trachoniedusjp,* and 
are distinguished by the fact tliat their ])rimi(ive tentacles Iteai- a<lliesive 
disks upon their aboral sides near their distal extremities. These primitive 
tentacles are retained throughout life, and project from the sides of the 
bell above the nmrgin. The marginal, or "velar," tentacles are ]»hyl()genetic- 
ally recent, and arise quite late in ontogeny. 
A study of the ontogeny of Cubaia and Olindias shows that the adhesive 
disks of their primitive tentacles are formed from modified nematocyst cells 
which gradually group themselves so as to form a cuj)-shaped or pad-like 
cluster. 
ANALYSIS OF THE GENP^RA OP 0LTND1AD.15. 
GENERA. 
Gonionemus . 
Cubaia 
Vallentinia . . 
Olindias 
Olindioides . . 
GONADS. 
CANALS. 
TENTACLES. 
Of one sort only. All liave I I 
adhesive disks and project Ribbon-like, folded sinuously. 4 radial canals only, 
from sides of bell. | j 
Two .sets of tentacles, one 
.set projecting from sides 
of bell ; other set arising 
lower down from bell 
margin. 
Papilliform. 
Sao like . . . . 
Papilliform . 
6, ribbon-like. 
4 radial and numer- 
ous centripetal ca- 
nals. 
6 radial and numer- 
ous centripetal ca- 
nals. 
Cubaia aphrodite, Mayer. 
Figs. JfS-J,9, Plate V. 
Mature MvduHa: Figs. 45-49. Bell slightly flatter than a hemisphere and 
about 12 muL in diameter. About eighty tentacles. About twenty of these 
project from the sides of the bell in a zone above the bell-margin, tiieir en- 
todermal axes extending through the gelatinous substance of I he bell. These 
tentacles are ringed at regular intervals with al)out eight nodular swellings 
containing nen\atocvsts. On the aboral side near the distal end of each 
* See Goto, 1903 ; Mark Anniversary Volume ; also Perkins, 1003 ; Proc. Acad. Nat. Sci. Phil- 
adelphia, 1902, p. 750-790. 
