ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 377 



relationsliip of this genus to other known groups. It seems to be most 

 closely allied to the aspidophorous group of the Polyzoa ; and, for the 

 present, must be regarded as an aberrant Polyzoon. 



Ovicells of Cyclostomatous Bryozoa.* — Mr. A. W. Waters thinks 

 that the ovicells of cyclostomatous Bryozoa are important characters, 

 so that it is to be regretted that so little is known about them. He now 

 describes and figures those of three of the species found by the 

 ' Challenger' ; the result of the examination of Idmonea fissurata Busk 

 is to remove it to the genus Hornera. In addition to I. irregularis and 

 I. milneana, Mr. Waters has some notes on I. Meneghini. 



Ovicells of Lichenoporse.t — The same author has notes on the ovicells 

 of some Lichenoporse ; this contribution is of importance, as in the third 

 part of Mr. Busk's British Museum Catalogue, and in the same author's 

 ' Challenger' Eeport, no notice is taken of these structures. 



Formation of Statoblasts in Plumatella.J — Herr F. Braem, in the 

 continuation of his researches,§ has been able to detect the passage of 

 ectodermal cells into the funiculus to aid in the formation of the stato- 

 blasts of Plumatella. In consequence of this immigration, the funiculus 

 swells up at its point of origin and represents a multicellular germinal 

 stock from which the first statoblast begins to be constricted off. In 

 later stages the connection of the ectodermal material of the germ-stock 

 with the integument becomes lost. As the immigration is effected 

 rapidly, it is not easy to demonstrate the passage of the cells, and, 

 further, the mode of development of the colonies appears to vary with 

 the period of the year. 



Delagia Chsetopteri. || —From notes of Prof. J. Joyeux-Laffuie and 

 Prof. E. Ehlers it seems clear that the Bryozoon described by the former 

 under the above name ^ was named Hypophorella expansa by the latter 

 in 1876. 



Arthropoda. 

 a. Insecta, 



Embryology of Insects.** — The first subject dealt with by Herr N. 

 Cholodkovsky is the development of the external form in the embryos 

 of Blatta germanica. The species recommended itself as appearing to 

 be one which was very suitable for the determination of some unsolved 

 problems in the embryology of the Hexapoda. The cocoon offered 

 considerable technical difficulties, which were got over by placing 

 cocoons, opened at either end, for from eight to twenty-four hours in 

 Perenyi's fluid, then in 70 per cent., and then in 90 per cent, alcohol. 

 The chitinous capsule of the cocoon could then be removed with needles, 

 and the eggs, as a rule, be isolated without injury. The egg has the 

 form of an elongated plate, near the straight margin of which lies the 

 germinal band, while the other surface is covered by undifferentiated 

 blastoderm. The latter is not at first continuous, but consists of 

 separate flat cells, which are, later, used to form the serous investment. 



* Joum. Linn. Soc. Lond., xx. (1889) pp. 275-80 (1 pi.). 

 t T. c, pp. 280-5 (1 pi.). 



X Zool. Anzelg., xil. (1889) pp. 64-5. § See this Journal, 1888, p. 937. 



II Arch. Zool. Exper. et Gen., vi. (1888) pp. xliv.-vi. 

 Tf See thia Journal, 1888, p. 936. 

 ** Zeitschr. f. Wiss. Zool., xlviii. (1889) pp. 89-100 (1 pi.) 



