ZOOLOGY. 771 



■ Under the heading of " classification " (p. viii) Professor Mcintosh 

 states that " the large number of new forms brought within our knowl- 

 edge by the Challeuger would have been supi)osed to lead to a note- 

 worthy change in classification, but from the first it was apparent that 

 no new family was required. All the types fell under the groups already 

 constituted, and which have been very satisfactorily given by Malmgren 

 in his Annulata Polychceta " (1867). Much " experience has not as yet 

 shown the necessity for any material change." It is admitted, however, 

 that "there are some forms, such as the genus Eulepis" (retained in 

 Polynoidse) which almost merit the distinction of a separate family, but 

 they have only recently been discovered and may properly be left for 

 further investigation." 



Two hundred and twenty new species are described by Professor Mc- 

 intosh. 



ARTHKOPODS. 



Merostomes. 



Embryology and morphology of Limiilus. — The horse shoe crab, or Lim- 

 ulus, has been the subject during the past year (as in previous years) of 

 investigation with reference to its embryology, morphology, and sys- 

 tematic relations. Of American naturalists. Dr. J. S. Kingsley has con- 

 tributed an important memoir on the embryology of Limulus to the 

 "English Quarterly Journal of Microscopical Science" (v. 25, pp. 521-576, 

 3 pi.), and Prof. Henry L. Osborn, Dr. W. K. Brooks, Mr. A. T. Bruce, 

 and Mr. W. H. Howell have communicated preliminary notices of iu- 

 vestigatons to No. 43 of the " Johns Hopkins University Circulars." 

 One, by Professor Osborn, is on the "Metamorphosis of Limulus poly- 

 phemus^^ (p. 1), a second, by Dr. Brooks and Mr. Bruce, is an " Abstract 

 of Eesearches on the Embryology of Limulus polyphemus " (pp. 2-4), and 

 a third, by Mr. Howell, is " On the Chemical Composition, &c., of the 

 Blood of Limulus polyphemus " (pp. 4, 5). Dr. A. S. Packard has also 

 published in the American Naturalist (v. 19) a supplementary memoir 

 on certain points of the embryology of the same species. Important 

 memoirs have been likewise published by Prof. E. Ray Lankester and 

 several associates or students, in the " Quarterly Journal of Microscop- 

 ical Science," and the " Transactions of the Zoological Society of Lon- 

 don." 



Arachnids. 



Sense organ in legs of spiders. — The peculiar structural modifications 

 of the legs which have been observed in certain spiders by Bertkau and 

 Dahl, and considered to be sensory organs, have been studied anew by 

 Professor Schimkenitscli. The structures in question have been found 

 in most of the leg joints in a number of spiders, and in both males and 

 females. They are superficially thin chitinous plates with thickened 

 borders, whose opx^osite sides are connected by parallel thickenings, 



