INVERTEBRA.TA, CRYPTOGAMIA, MICROSCOPY. ETC. 897 



similar, ciliated cells) was not tlic gastrula, but the pm-cnchjmella, or 

 planula with internal mass of i^arenchyma, and that this arose from the 

 blastula, by some of the cells of the latter losing their cilia and making 

 their way into the blastocele, like the reproductive cells of Volvoz. 

 This theory, according to which the gastrula is a secondary larval 

 form, is supported by the absence of a gastrula stage in the lower 

 sponges and ccelenterates, by the fact that the gastrulae of different 

 animals are not homologous, and by the occurrence of pseudogastrulae. 



Development of Horny Sponges.*— Dr. C. Keller, of Ziirich, 

 records the following observations on the development of Chalinula 

 made at the Zoological Station, Naples. 



Multiplication is both asexual (by buds) and sexual : the breeding 

 season being in March and April. The sexes are separate : before 

 sexual maturity both sexes have a brownish-yellow colour ; at the 

 breeding season, the female becomes rose-red, and finally yellowish 

 red. It takes about twelve to fifteen hours for the larvse to escajie : 

 afterwards tiie sponge rapidly dies down. The egg is surrounded 

 with a special follicular investment. Yolk-division is amphiblastic 

 (total, but unequal) : no cleavage cavity was observed. 



An amphigastrula was formed with an epiblast formed of a single 

 layer of flagellate cells, and giving rise to the adult ectoderm ; and a 

 hyj)oblast which forms both mesoderm and endoderm of the adult. 



Protozoa. 



Reticularian RMzopods.f — Mr. H. B. Brady continues his account 

 of the ' Challenger ' specimens. The greater part of the paper is 

 taken up with systematic descriptions of species, of which the follow- 

 ing are new : — Frondicularia compta, Fldbellina foliacea, Ramulina 

 globidifera, Uvigerina punda and U. interrupta, Sagrina virgula, and S. 

 divaricata, Spirillina incequalis, S. limhafa, and S. obconica, Planorbulina 

 echinata, Glohigerina cequilateralis, G. digitata, and G. conglobata. 



The part of the paper of greatest general interest is the con- 

 cluding section, "Notes on Pelagic Foraminifera." The forms at 

 present known to occur at the surface are : — Glohigerina buUnides, 

 ivjiata, rubra, sacciilifera, conglobata, and aquilateralis ; G. (Orbulina) 

 universa ; Hagtingerina pelagica, do. var. Murrayana ; Pullenia oblique- 

 lociilata ; Sphceroidina dehiscens ; Candeina nitida ; Pulvinulina 

 Menardii, do. var. tumida, P. Canariensis, crassa, and Micheliniana ; 

 Cymbalopora bulloides ; and Chilosfomella ovoidea. 



As to the question whether Foraminifera live both at the bottom 

 and at the surface, the author summarizes the more important facts as 

 follows : — 



1. "We have positive evidence that Foraminifera do live at the 

 bottom of the deep sea, from the common occurrence at great depths 

 of certain forms with composite or ai-enaceous tests ; and we have 

 negative evidence in the same direction in the entire absence from 



* ' Zool. Anzeiger,' ii. (1879) p. 302. 



t ' Quart. Journ. Micr. Sci.,' xix. (1879) p. 2G1 ; see also this Jourual, a7ite, 

 p. 276. 



VOL. II. 8 O 



