Mr. Alexander Agassiz in 1879 and have been described by Dr. Dall and by MM. Bouvier and Fischer. More recently several specimens of P. Beyrichii have been taken off the coast of Japan from a depth of 70 to 80 fathoms and have formed the basis of a description by Mr. Martin F. Woodward, which appears in a recent number of the 'Quarterly Journal of Microscopical Science' (March, 1901).
As might be expected from its great antiquity, Pleurotomaria presents a number of primitive characteristics which throw considerable light upon the affinities of the different groups of the Mollusca. Possessing two gills, two kidneys and two auricles to the heart, it belongs to the suborder termed Diotocardia zygobranchia, a group which also includes the genera Haliotis and Fissurella; and which, on account of the approximation of its members to a greater degree of bilateral symmetry than is found in the majority of the Gasteropods, is generally regarded as being the most primitive group of its order. In several respects, however, Pleurotomaria is found to possess structural characters of a more primitive nature than those found in other diotocardiates and appears to stand in closer relation to the main line from which the monotocardia have diverged than any other recent genus.
It would require more space than can be allowed here to mention all the important results obtained by Mr. Woodward, but attention may be called (1) to the primitive condition of the nervous system, whose cells are scattered along the various connectives and are not aggregated into definite ganglia—a condition recalling that obtaining in the Amphineurous Mollusca; and (2) to the peculiar position of the supporting skeleton of the gills, which, taken into consideration with the occurrence of a well-developed spinal caecum attached to the stomach, suggests to Mr. Woodward's mind a comparison and possibly an affinity with the Cephalopods, in which similar conditions exist.
SCIENTIFIC ITEMS.
The students of the University of California held memorial exercises in honor of the late Professor Joseph Le Conte on February 26, the anniversary of his birth. Funds are being collected to assist in the erection of a granite lodge which the Sierra Club proposes to construct in the Yosemite Valley as a memorial to Dr. Le Conte.—Plans have been formed for the erection of a memorial tower and meteorological station in honor of Dr. J. P. Joule, F.R.S., at Sale, Cheshire, where he lived from 1872 to the time of his death in 1880.
Professors William James and W. Wundt, the eminent psychologists, and Professor James Dewar, the eminent chemist, have been elected honorary members of the New lork Academy of Sciences.—Professor Hermon C. Bumpus has been appointed director of the American Museum of Natural History, New York.—Professor W. H. Brewer, for thirty-seven years professor of agriculture in the Sheffield Scientific School of Yale University, will retire from the active duties of the professorship at the end of the present academic year.
It will be remembered that Mr. J. Pierpont Morgan gave last year $1,000,000 for the rebuilding of the Harvard Medical School. An equal sum has recently been given by Mr. John D. Rockefeller, and nearly the same amount has been given by others, including $250,000 from Mrs. C. P. Huntingdon and $100,000 from Mr. James Stillman.
