382 — Mr. Hoee’s Observations on the Spongilla fluviatilis, 
ness I had the pleasure about eighteen months ago to witness the living polypes 
in that Zoophyte, and to observe for the first time the actual presence of the 
cilia ranged along their tentacula, and the extremely rapid and vibratory mo- 
tions of those organs in the water. That author has made known many 
curious and important facts respecting the Binosculous Ciliotentacular Zoo- 
phytes* in his interesting memoir, which is published in the Philosophical 
Transactions for 1837, where, at p. 412, writing on the gemmules of that spe- 
cies, he says, “It would be impossible to explain the variety of motions which 
the gemmules are capable of executing, were it not obvious how complete is 
their control over the action of the cilia, which are their sole locomotive or- 
gans. They generally swim with the convex part forwards, and with the 
greatest rapidity. Sometimes they simply rotate upon their axis, or they 
tumble over and over; or, selecting a fixed point, they whirl round it in rapid 
circles, carrying every loose particle after them. Others creep along the bot- 
tom of the watch-glass upon one end, and with a waddling gait; but generally 
after a few hours all motion ceases, and they are found to have attached them- 
selves to the surface of the glass.“ He further adds, “The parenchyma of the 
gemmules has a contractile power, somewhat like that of Hydra, but less in 
degree, by which the form of the body is occasionally altered.” 
* These are the Ciliobrachiate Polypi of Dr. A. Farre. 
(tentacula) of Zoophytes as presenting the principal and most characteristic organs by which those 
animals ought to be classified in strict accordance with their natural conformation. The Ciliotentacula 
would include a large and separate order, composed of the genera Flustra, Cellularia, &c. The Pinni- 
tentacula would comprise those Zoophytes whose teñtacula are pinnated ; for instance in the Gorgoniæ, 
Pennatule, &c., where the tentacles are furnished with small pinnæ. The Tubitentacula, the Actinie, 
the Madrepore, and the rest which possess tentacula in the form of siphons or hollow tubes perforated 
at their extremities, The Planitentacula, which is synonymous with a part of Dr. Farre’s Nudibra- 
chiate Polypi, would comprehend those Zoophytes whose tentacles are quite plain and devoid of any 
lateral excrescences or appendages, as Tubularia, Coryne, &c.; and the order Noditentacula, the genus 
Hydra, and family of the Sertulariade, which have those organs covered with little knots, nodules, 
or projections. But the class Zoophyta itself should be divided into two subclasses ; viz. 1. Binoscula, 
or the Zoophytes that have distinctly two holes or orifices, one of which is their mouth, and the other 
their anus; to this belongs my first order. And 2. Unoscula, those with one orifice, serving both for 
their mouth and anus; herein are supposed to be included all the four latter orders. Additional ex- 
aminations, indeed, guided by some anatomical skill, are yet wanting for the purpose of completin 
this tentacular arrangement, which would then be of considera 
ble use in more clearl defini 
of the most important characters that belong to those very remarkable animals, y ng several 
I have long considered the tentacles 
