572 



POPULAR SCIENCE MONTHLY. 



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 ap- 

 pears 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 MoUusca. Possessing two gills, two 

 kidneys and two auricles to the heart, 

 it belongs to the suborder termed Dioto- 

 cardia 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 primi- 

 tive 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 im- 

 portant results obtained by Mr. Wood- 

 ward, but attention may be called ( 1 ) 

 to the primitive condition of the nerv- 

 ous 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 support- 

 ing skeleton of the gills, which, taken 



into consideration with the occurrence 

 of a well-developed spinal caecum at- 

 tached to the stomach, suggests to Mr. 

 Woodward's mind a comparison and 

 possibly an affinity with the Cephalo- 

 pods, 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 sta- 

 tion 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 l^ork Academy of 

 Sciences. — Professor Hermon C. Bum- 

 pus has been appointed director of the 

 American Museum of Natural History, 

 New York. — Professor W. H. Brewer, 

 for thirty-seven years professor of agri- 

 culture 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 Har- 

 vard Medical School. An equal sum 

 has recently been given by Mr. John 

 D. Rockefeller, and nearly the same 

 amount has been given by others, in- 

 cluding $250,000 from Mrs. C. P. Hunt- 

 ingdon and $100,000 from Mr. James 

 Stillman. 



