456 Miscellaneous. 
are similarly situated; and the products of the latter are poured 
directly into the body-cavity. The existence of a mesentery and 
the mode of development of the buds and of the embryo in the 
ovum demonstrate very clearly the Enteroccelous type of the 
Ascidia. The author confirms the opinion that the endostyle is a 
gland, and states that the circulation of the blood takes place ex- 
clusively by lacune. 
The reproductive apparatus of the Ascidia was almost entirely 
unknown. The author has paid particular attention to it, and has 
obtained truly important results from his careful observations. 
Particularly noteworthy are the formation of a special oviduct in 
the Botryllide analogous to that of the Salpe, and the peculiar 
form of the testis in the Aplidia, which induced Milne-Edwards 
and Giard to regard the postabdomen of those animals as a true 
ovary. He also gives a very exact description of the structure of 
the postabdomen, in which are recognized all the elements of the 
fundamental lamelle of the animal, namely ectoderm, endoderm, and 
peritoneal sacs. . 
In a young Botryllid the author has seen the nervous ganglion in 
direct continuity with the prolongation of the vibratile fossa. ‘The 
muscular system is composed of smooth fibres situated beneath the 
ectoderm, between this and the parietal lamella of the peritoneum. 
Finally, the author confirms the discovery of Metschnikoff of the 
origin of the. buds of the Botryllide from the parietal lamella to the 
right and left, and describes minutely their various stages, and 
especially the formation of the enterocele. In connexion with this 
he refers to the memoir of Kowalevsky upon the development of 
the simple Ascidia, and demonstrates that in these also the perito- 
neal sacs are not developed from the ectoderm, as maintained by the 
Russian naturalist, but are rather derived directly from the intes- 
tine. Hence he draws the final conclusion that the Ascidia certainly 
belong to the Enteroccelous type.—Atti R. Accad. dei Lincei, Trans- 
unti, vol. vi., 1881, p. 14. 
On the Vitality of the Germs of Artemia salina and Blepharisma 
lateritia. By M. A. Cerrus. 
After inundations or heavy rains the sudden appearance of cer- 
tain lower Crustaceans (Apus, Branchipus) has frequently been 
noticed ; aud it has been justly concluded that the ova of these 
Crustaceans had the property of remaining uninjured under very 
- different conditions ofmedium. An experiment that I have recently 
made upon Artenia salina leaves no doubt upon this point,’ and 
proves that the alternations of desiccation and moisture to which the 
ova of this Crustacean are subjected may be prolonged with impu- 
nity during several years. 
In March 1878 I collected salt water from the Chott Timrit, 
near Boutinelli (Province of Constantine, Algeria). A rapid exa- 
mination (all that was possible at the moment) enabled me to ascer- 
