ZOOLOGY. 283 



the basal joint of each. These areas constituted respective- 

 ly the scraper and the rasp : the former was tolerably thickly 

 but regularly beset with stout, conical sharp spinules curved 

 like a tiger's canine, only more towards the points, some of 

 which terminate in a long limp hair; the latter thickly stud- 

 ded with minute tubercles shaped like tops of mushrooms. 



It now remains for Mr. Wood or some one else to discover 

 the ears of the scorpion ; for if they can produce a sound, they 

 must have ears to hear it, and none are as yet known to ex- 

 ist in the Arachnida. 



In insect anatomy, an elaborate memoir on the so-called 

 ventral vessel of the Lepidoptera, with observations on the 

 sympathetic nerve, has been published in Hofmann's Nie- 

 derldndisches Archiv fur Zoologie (Bd. iii., Heft 2, 1876). 

 The examination of these organs was made in examples of 

 all the families from the Papilionidcv to \\\QPteroplioridcv. 



A memoir on the internal spinning apparatus of Lepidop- 

 terous insects, by Helm, appears in Siebold and Kolliker's 

 Zeitschrift (vol. xxvi.). 



Dr. O. J. B. Wolff has published in the " Nova Acta Acad. 

 Natur. Curios.," vol. xxxviii., Dresden, 1876, a memoir (illus- 

 trated with eight plates) on the minute anatomy of bees, 

 with reference especially to the mechanism of the mouth- 

 organs and respiratory organs of the thorax and abdomen. 



An elaborate and richly illustrated memoir on the sense-ap- 

 paratus of the Orthoptera, by Dr. V. Graber, appears in the 

 Transactions of the Imperial Academy of Science of Vienna. 



Dr. C. Chun has studied the structure, development, and 

 physiology of the rectal glands of insects. His memoir, with 

 three plates, is in the Transactions of the Frankfort Scien- 

 tific Society. 



Evolution. 



Among communications of theoretical interest are articles 

 by Mr. W. H. Dall, " On a Provisional Hypothesis of Salta- 

 tory Evolution," and by Dr. W. K. Brooks, entitled "A Pro- 

 visional Hypothesis of Pangenesis," both published in the 

 American Naturalist. 



Parthenogenesis. 



That fishes and other vertebrates have in two or three ob- 

 served cases been partially developed without fecundation 



