402 DR. A. FARRE ON THE STRUCTURE OF THE CILIOBRACHIATE POLYPI. 
ing stem has a remarkably definite character (fig. 2.). Between every dichotomous 
division is a joint bearing three cells, which, when they drop off leave a circular 
foramen. The cells are strictly unilateral upon the stem, and diminish in size very 
regularly towards the growing extremity ; the last few being mere buds from its 
surface. Within the stem may be seen a number of transparent, circular bodies of 
a tolerably uniform size, that appear to be attached to the inner surface. They very 
much resemble in appearance the granules which may be seen through the cell 
attached to the membranous parietes of the animal itself. These latter are smaller 
than those in the stem, and more scattered. I have not ascertained the use of either. 
Ellis was, I believe, the first to notice in this species what appears to be a direct 
medium of communication between the animals themselves. It consists of a thread 
of a darker substance than the rest of the stem, running within its upper surface im- 
mediately below the base of the cells. Ellis states* that the slightest movements of 
the animals were communicated to this substance, an observation that I have not 
been able to confirm ; but my specimens were not very lively. The point is one of 
interest and worthy of further investigation. 
PLATE XXIII. 
Valheria cuscuta, Flem., Brit. Anim. p. 550. gen. Ixx. 196. 
Syn. Corallina cuscutce forma, Ellis, Corall. N. 26. pi. xiv. c. C. 
Sertularia cuscuta, Linn., Gmel. p. 3852. No. 18. and Muller, Zool. Dan. 3 S 
p. 62. t. 117- f. 1—3. 
Cuscutaria cuscuta, Blainv. Diet, des Scien. Nat. p. 461. 
Vesicularia cuscuta, Thomp. Zool. Research. N. IV. pi. ii. 1. 
This is the most minute species that I have met with. Its creeping stems are found 
closely adherent to the filamentous ramifications of a species of Ceramium, on which 
it grows parasitic, with much of the habit of Dodder, whence its trivial name (fig. 1. 
and 2.). 
It has been placed in the same genus with the species last described, but differs 
from it, and also from Bowerbankia, in the entire absence of the manducatory organ; 
a difference which it is of great importance to observe with reference to a natural ar- 
rangement of the class'^. 
The ciliated tentacles are eight in number, slender, and often widely spread, ex- 
hibiting a good view of the oral aperture (fig. 4. a.). 
The alimentary canal is here of some length, and acquires a considerable sigmoid 
flexure when the animal is at rest (fig. 5.). The intestine near its termination pos- 
sesses a decided rectal enlargement, which is very distinct even when empty (fig. 5. e.). 
* Essai sur l’Hist. Nat. des Corall. p. 36. 
f I have for this reason removed it from Vesicularia, and adopted the name previously given to it by 
Dr. Fleming. 
