582 The American Naturalist, [June, 
and forms a circular nerve around the body. ‘The circulatory system 
is closed. It consists of two plexuses, one in the lophophore, and the 
other in the lower lip. These are connected with a reservoir or dor- 
sal tube lying on the cesophagus, and at the junction of reservoir and 
plexuses there is a large blood sinus almost completely surrounding the 
brain. The animals are dicecious, the generative organs occurring at 
the points of origin of the ventral retractors. Mr. Shipley thinks that 
the evidence presented by Phymosoma lends additional weight to the 
view that Phoronis should be regarded as related to the Gephyrea 
inermia, 
Molluscs of the Albatross Explorations.2—The United 
States Fish Commission steamer Albatross made collections on her 
voyage from the Chesapeake through the Straits of Magellan and 
north to California, Mr. Dall has reported upon part of the mol- 
luscs. As might have been expected, the cruise resulted in many 
novelties and varieties in forms from depths of over one hundred 
fathoms. The account opens with an interesting discussion of the 
environments of deep sea life, and its effect upon the molluscan fauna. 
It is interesting to note that molluscs which belong to phytophagous 
groups are, from the absence of plant life in the deep sea, obliged to 
put up with a diet of Foraminifera, and as a result the digestive organs 
are greatly increased in calibre, the termination of the intestine pro- 
longed beyond the body, so that the fæces are deposited away from 
the gills. Deep sea mollusc shells are remarkably free from those 
countersunk holes produced by the radula of carnivorous gastropods, 
a fact which leads the author to conclude that they do not live in per- 
petual conflict with each other; that the struggle is against environ- 
ment rather than against molluscan enemies. The systematic portion 
begins with the brachiopods (why this association of brachiopods and 
molluscs?) and then follow acephals and gastropods. In the text are 
numerous interesting points, among them the fact that the embryos of 
Scaphella magellanica possesses a membranous protoconch, the exist- 
ence of which explains the peculiar apex of the shell of the adult. 
"2 Proc. U. S. Nat. Mus., XII., 1889 [1890]. 
* Jenaische Zeitschrift, XXIV., p. 227, 1890. 

