BAHAMA MEDUSAE. 5 
Gonionemus, Ciibaia, Vallentinia, Olindioides and Olindias are closely re- 
lated genera, which may be grouped into one family, the Olindiada*.* The 
marginal (velar) tentacles of Cubaia and Olindias are secondary and arise 
quite late in ontogeny. The distinguishing feature of the Olindiada' is the 
development of a pad-like cluster of modified nematocyst cells upon the abo 
ral side, near the distal extremity, of each and all of the primitive tentacles. 
These pad-like expansions may serve as adhesive disks or organs of tempo- 
rary attachment. 
A study Avas also made of the phenomenon of asexual budding in medu- 
sae. One of the most interesting examples is afforded by Eucheilota para- 
doxica, which is the only Leptomedusa known that produces an asexual 
generation of medusae by a direct process of budding. These daughter me- 
dusae are derived from both entoderm and ectoderm of the gonad of the pa- 
rent (Fig. 65, Plate VII). 
We have, therefore, a graded series of phenomena in the asexual produc- 
tion of medusa buds by hydromedusae. In forms where the ectoderm and en- 
toderm are both thin-layered and of about equal thickness, such as in the Sar- 
si«rfrte and /?J, /)rt>rt(?oj?ic«, both entoderm and ectoderm take an equal share in 
the formation of the bud. In forms such as IJathkea octopunctata and 
Lizzia Olapereidei, according to Chun, 1895, a different condition is observed, 
for the medusa buds are formed entirely within the ectoderm of the parent, 
although the gastro-vascular cavity of the bud finally acquires a connection 
with that of the parent; the entoderm of the bud becoming continuous with 
that of the parent manubrium. 
In Bougainvillia niobe from the Bahamas, however, the ectoderm is very 
thick, and the budding medusae are developed within it alone; the entoderm 
remaining inert and passive during the growth of the bud, and no connection 
ever being established between the gastro-vascular cavities of the bud and the 
parent. (See Figs. 15-15c, Plate II.) This result may be regarded as due 
to a gradual process favored by the thickness of the ectoderm, which pre- 
vented the deep-lying entoderm from taking an equal share in the formation 
of the bud, until finally, as in B. niobe, it remains passive thnmghout the pe- 
riod of the formation of the bud. Medusa? produced from ectoderm alone 
may, therefore, be phylogenetically homologous with mednsje produced bv 
* Goto, S. 1903 ; Mark Aimiversary Volume. 
