568 



SCIENCE. 



[N. S. Vol. II. No. 44. 



markable for the full recognition given to 

 paleontology as a branch of zoology. 



Prof. Sedgwick (Cambridge) read a paper 

 on Cellular Theories, in which he pointed 

 out the morphological inconsistencies and 

 absurdities to which the prevalent theories 

 lead. 



Prof. Hensen (Kiel) made a report upon 

 his Plankton studies, of which he consid- 

 ered the most interesting result to be the 

 fact that the method of measuring percent- 

 ages of various animals collected at different 

 depths by fine, self-closing nets proves to 

 be exact and may be employed as a basis 

 for further investigations. 



Prince Roland Bonaparte spoke of the 

 researches in marine zoology made on the 

 steamer ' Roland,' which he had placed at 

 the disposal of M. de Lacaze Duthier. 



Prof. Liitken (Copenhagen) spoke of the 

 expedition for exploration of the great 

 depths of the subarctic seas. 



Prof. Scott (Princeton) made some re- 

 marks upon the relation of individual va- 

 I'iations to the origin of species. 



Prof, de Zograf (Moscow) gave a paper 

 upon the origin of the lacustrine fauna of 

 European Russia. The Russian lakes may 

 be divided into four groups, the first de- 

 rived from a bay of the White Sea and 

 from a glacier ; the second and third are 

 the remains of glaciers. These three regions 

 have the same limits as the three glaciers 

 of the latter glacial periods of Geikie. The 

 fourth group is derived from the Black and 

 Caspian and other ancient seas which once 

 covered southern Russia. 



M. Vaillant (Paris) spoke of bis re- 

 searches on the structure of the osseous 

 spine in the carp 



Prof. Emery (Bologna) made a commu- 

 nication upon the polymorphism of ants 

 and upon alimentary castration, defending 

 the principle that the sterility of neuters 

 and their different forms are chieflj' due to 

 the way in which the larvffi are fed. 



The paper of M. Wasmann (Exaeten) 

 dealt principalljf with the determination 

 and classification of the ants and termites, 

 giving the criteria of division with especial 

 reference to those morphological characters 

 which are of an adaptive nature. 



At 4:30 P. M. the members of the Con- 

 gress were received, by invitation of the 

 Municipal Council of Ley den, in the Town 

 Hall, where the Burgomaster welcomed 

 them in a graceful speech, to which the 

 President, Dr. Jentink, responded. The 

 day was very agreeably ended bj' a concert 

 at Katwijk given to the Congress. 



TUESDAY, SEPTEMBER 17TH. 



Prof. O. C. Marsh (New Haven) gave a 

 paper upon the affinities and classification 

 of the Dinosaurian Reptiles, illustrated by 

 diagrams of A'Hosaurus, Hallopus, Trieeratops, 

 Stegosaiirus and others, and of footprints, 

 one of which shows a difference in the num- 

 ber of digits of the fore and hind feet. A 

 new classification of the Dinosauria was pro- 

 posed. 



M. Biittikofer (Leyden) gave an account 

 of the Dutch expedition to the interior of 

 Borneo. 



Prof. Liitken spoke of the investigations 

 made in Denmark upon the fossil mammals 

 of the Brazilian caverns. 



Dr. C. W. Stiles (Washington) read a 

 paper on the ' Revision of the Leporine 

 Cestodes,' based upon the original types of 

 European species and upon extensive 

 American material. None of the European 

 species have been found in North America. 



M. S Goto (Tokio) gave a short report 

 on some ectoparasitic Trematodes from 

 the Atlantic coasts of the United States and 

 communicated also a case of synonj'my 

 of an European species. The species 

 treated of are as follows: (1) Tristomum 

 Iseve, Verrill. Examination of an original 

 specimen shows that this is identical with 

 the species described under the name 



