323 
found in the stomachs of certain Mollusca, 
Clam, &c. ; and Dr. Hooker in the ' Botany of the Antarctie Voy- 
age ' states, that the stomachs of Balpoe and other (especially of 
the naked) Mollusca invariably contain Diatomaceay sometimes 
several species. These Salpce were washed up in masses on the 
pack ice, and in decay they left the snow covered with animal 
matter impregnated as it were with Diatomacece. He found that 
the contents of the stomach of every Salpay between the latitudes 
of the North Tropic and 80° South, invariably contained the re- 
mains of these minute plants. Dictyocha aculeata was universally 
observed in the stomachs of those found off Victoria Barrier. 
Mr. Lee has found them abundant in the stomach of the com- 
mon Barnacle. 
The following notes of species detected in the stomachs of 
different species of Ascidia and of the freshwater Mussel {Mya 
margaritiferay L.) may be worthy of record. They do not appear 
to have the same discrimination as to their prey which the fishes 
would seem to exercise, every object, whatever be its nature, 
coming within the sphere of the currents produced by the eilia, 
is swallowed, provided its size be not too great. The Ascidia 
examined were from depths varying from twenty-five to thirty 
fathoms, and five to six miles from land. 
A time was when there would have been some hesitation in 
offering to the Society such a communication as the present, 
owing to the conviction that some of the organisms to which it 
has reference really belonged to the animal kingdom. The very 
important discovery made by Mr. Thwaites, that they present 
examples of conjugation like Zygnemay &c., leaves their true na- 
ture no longer a doubtful question. There may still be some 
dispute respeeting the position occupied by such forms as Cosci- 
nodiscuSy ActinoptychuSy &c. ; but if it be admitted, and there 
seems no reason for hesitation, that such genera as Meloseira and 
its allies are true plants, it will not be difficult to understand also 
the nature of those just mentioned, the transition from the one 
to the other being obvious. 
Diatomacea found in the stomachs of, different species of 
Ascidia : — 
Eunotie^B. 
Epithemia Sorex, Kg. ? 
FragilariecB. 
Fragilaria pectinalis, Ehr. 
Diatoma flocculosum, Jg. 
Meloseirecc. 
Meloseira sulcata, Kg. 
M. Jurgensii, Ag.1 
SurirellecB. 
Surirella ? 
Synedra laevis, Ehr. 
Cocconoidece. 
Cocconeis Pediculus, Ehr. 
Doryphova amphiceros, Kg. 
AchnanthecB. 
Achnanthes longipes, Ag. 
CymhellecE. 
Cymbella maculata, Kg. 
Gomphonemece. 
Gomphonema pohliaeforine, Kg. 
22 * 
