GERMANY. 19 



On the Vas Deferens; with figures— p. 473-489. (Hirt) On the numerical 

 proportion between the White and Eed Blood cells; with a plate — p. 174-199. 

 (Luschka) The sensitive branches of the nerves of the Nervus Hypoglossus 

 in man ; with a plate — p. 62-82. The filaments which run to the Hypoglossus, 

 whether direct, or through the medium of the Ganglion submaxillar, as origi- 

 nating from the Lingualis, have a sensitive function, and are recurrent in, or on 

 the main stem of the Hypoglossus, to the spot where they are destined to diffuse 

 themselves in the Periphery. (Same; On the presence of a Supraclavicular 

 Muscle in man ; with a plate— p. 282-285. Vertebrate. (Busch) Vital 

 phenomena in the Pigment cells ; with a plate — p. 415-424. Observed in larvae 

 of frogs and newts. (Mueller) Embryology of Petromyzon; Preliminary re- 

 port — p. 323-329. (Reichert) On the Micropyle of fishes' eggs ; and on a pe- 

 culiar structure, not before discovered, of the mature and impregnated eggs ; 

 with plates — p. 83-124. (Same) On the Mueller-Wolffian bodies in embryos 

 of fishes, and the so-called rotations of the yelk in the impregnated egg of the 

 Pike ; with figures — p. 125-143. (Remak) On the terminations of the Nerves 

 in the Electric organs of the Torpedo — p. 467-472. Invertebrate. (Filippi) 

 On the origin of Pearls; from the journal Cimento, Fasc. IV. Turin, 1852; 

 translated by Kiichenmeister, with Notes from his own investigations — p. 251-268. 

 (Same) A word more on the formation of Pearls; in reference to Kuchen- 

 xueister's remarks — p. 490-493. (Kiichenmeister) On one of the most fre- 

 quent causes of the existence of pearls in the Elster muscles (Anodontes) ; 

 and a plan proposed for the artificial multiplication of pearls — p. 269-281. 

 Most of the pearls in question were found to have the body of a water-mite, Atax 

 ypsilophora, for their nucleus. (Schlossberger) Concretions in the organs of 

 Bojanus, from Pinna nobilis — p. 540-543. (Krohn) Observations on the de- 

 velopment of the Pteropoda, Heteropoda, and Echinoderma ; in a letter from 

 Funchal — p. 515-522. (Gegenbaur) On the Marginal bodies of the Medusas; 

 with a plate — p. 230*250. Great differences are found in the structure of these, 

 in going from the lower forms to the higher which are provided with a velum — 

 Medusidae — Rhizostomidae; and within the limits of the several groups there is 

 an evident progression from a lower to a higher type of organization in this re- 

 spect. The presence of a pigment spot in some of the higher forms makes it 

 less surprising to find in some an evident refracting lens, as in Nausithoe albida 

 Geg. ; in Garybdea marsupialis this attains a considerable size, with a distinctly 

 globular figure. The regular transition from this structure, and the iudubitable 

 analogy, to the vesicular form of the marginal bodies, with concretions enclosed, 

 but destitute of crystals, in the lower forms, in which they have been considered 

 as auditory organs, tends to cast some degree of doubt on this interpretation of 

 the phenomena. (Schultze) On the structure of the gelatinous disc of the 

 Medusae ; with two plates — p. 311-322. (Lachmann) On the organization qf 

 the Infusoria, and of the Vorticellae in particular ; with two plates — p. 340-398. 

 (Weisse) A little addition to Schneider's Contributions to the Natural History of 

 the Infusoria; with a plate— p. 160-164. On the en cystm en t of ClUorogonium 

 euclilorum, chiefly. (Lieberkuhnj Contributions to the Anatomy of the Infu- 

 soria — p. 20-36. (Same) On parasitic pouches attached to the larvae of Phry- 

 ganidae; from the Monthly Report of the Berlin Academy of Science, April, 

 1856; with figures — p. 494. (Same) On the development of Spongillae — p. 

 1-19. Addenda to the same ; with figures — p. 496-514. The following is a sum- 

 mary of the most important conclusions to which the author has come in the 

 course of this inquiry. The embryos are covered with a ciliary epithelium on the 

 entire upper surface : they proceed from the so-called conglomerations of germinal 

 granules ; as soon as the ciliated embryos attach themselves, they take the form 

 of the perfect Spongilla : the contractile cells of the latter are formed after the 

 loss of the germinal granules, partly in the ciliated embryo, partly after the dis- 

 appearance of the cilia ; this is what is called a " Generalio aequivoca" of the 

 cells, or an extracellular cell-formation : the siliceous spicules originate in the in- 

 terior of the cells, the corneous substance of the framework of the gemmule- 



