Mr. W. Clark on the Animal of Kellia rubra. 145 
to supply moisture to prevent the desiccation of the branchi of 
Kellia rubra, as well as those of the Littorina jugosa and petrea, 
and of the Patelle and Mytili, which, in many situations, are not 
submerged throughout the year; and I can affirm that I saw 
hundreds of some of the animals I have named from ten to twenty 
feet above the level of the highest spring-tide at any period of 
the year. How these animals exist is a mystery ; it is possible the 
saline particles in the air, and the fine spray carried by the winds 
to the rocks on which these animals are found, may supply suft- 
cient moisture for the branchize ; but can the animal from these 
materials extract sustentation ? There is no appearance of their 
descent to lower levels ; they appear to be fixtures ; and I am in- 
formed they are to be found in the same situation in all seasons. 
As for Kellia rubra, they exist in myriads in all the higher levels 
of the littoral zone, but im the very lowest they are not submerged 
for four hours during the twenty-four. 
These facts invalidate the doctrine of the branchial currents by 
cilia, and their having separate apertures of ingress and egress ; 
for what can be the use of them in Kellia rubra, when they neces- 
sarily must be interrupted for twenty hours out of the twenty- 
four throughout the year? It seems strange, according to Mr. 
Alder, that a special branchial orgau should be furnished by na- 
ture for a bivalve, which can better dispense with such a specialty 
than any other in existence. 
With my best thanks for your liberal insertion of my papers 
in the ‘ Annals,’ 
I remain, Gentlemen, your most obedient servant, 
WitiiaM Criark. 
Postscript.—To corroborate the conjecture stated above of 
the real uses of the anterior tubes of Kellia rubra and Kellia sub- 
orbicularis, | beg to add, that I have just examined a fine Kellia 
suborbicularis. I placed it on the umbones ; it immediately ex- 
serted and opened the tube, and by the aid of a powerful lens I ~ 
counted at its fundus fitecn largely developed ova, and I have 
not the slightest doubt that these anomalous animals, as regards 
reproduction, are furnished with these anomalous tubes to minister 
thereto; and I have further to state, that on submitting this ani- 
mal to my scalpel and to one of Mr. Ross’s best microscopes, I 
received the fullest confirmation of my conjectures, having found 
at the bottom of the ovarium resting on the fundus of the tube, 
ova in all states of development and fully-formed testaceous young. 
I have carefully preserved the shell and ovarium. Therefore 
Kellia rubra and Kellia suborbicularis are undoubtedly vivipa- 
rous; the only difference between the two is, that the young in 
Kellia rubra are fully developed m the ovarium, and only require 
the open tube-like fold for an oviduct, and to convey water to 
Ann. & Mag. N. Hist. Ser. 2. Vol. iv. 10 
