ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 437 



peristome, which is a disc lying transversely to the long axis of the 

 body, is next described ; it has but a slight power of retraction, and is 

 so far by no means comparable to the peristome of Stentor or Vorticella ; 

 the adoral ciliated plates aid in closing it. The account of the internal 

 structure is divided into descriptions of the body-substance, the nuclei, 

 and the vacuoles. 



After some notes on their life-habits, the author passes to a systematic 

 account of the forms that compose the family ; Amphorella, and Undella 

 are new genera, and twenty-nine new species are described. 



Spore-formation in Peridineae.* — Herr F. Schutt has made some 

 observations on the development of Peridinea3, which appear to him to 

 strengthen considerably the case against their being animals. 



(1) He corroborates, in regard to Geratium fusus and G. furca, the 

 observations of Bergh on the division of G. tripos. (2) Quite distinct 

 from the latter, a further process was observed which the author terms 

 spore-formation. The protoplasm retracts, rounds itself off, and secretes 

 a homogeneous sheath ; the original case bursts, a pear-shaped " sporan- 

 gium " issues, and divides into two. So far Peridinium spiniferum 

 Clap. Lach. But in Peridinium acuminatum Ehrbg., a further evolution 

 was observed. The daughter-cells, issuing from their sheath, were seen 

 to rest for a few minutes and then exhibited a flagelluni at one end. 

 Herr Schutt therefore calls them " swarm-spores," and compares his 

 results with the history of diatoms. Finally, he suggests that further 

 observations will show that the naked forms of Peridinese, e. g. Pouchet's 

 Gymnodinium gracile, are simply stages in the history of encased forms. 



Radiolaria.'j" — Under the title of part ii. of ' Die Badiolarien ' Prof. E. 

 Haeckel has published a ' Grundriss einer allgemeinen Naturgeschichte 

 der Badiolarien,' which consists of the introduction to the ' Challenger ' 

 Beport on Eadiolarians, to which are appended a ' Catalogus Badiola- 

 rium,' and a ' Clavis Generum ' ; the latter based on the keys in the 

 ' Challenger ' Beport. The seventy-four plates are a selection of those 

 of the atlas of the report. 



New Foraminifer.| — SI. J. Kunstler describes a remarkable new 

 Foraminifer found at Arcachon. The adult has an ovoid monaxial test, 

 one to two millimetres long, with the mouth at one pole ; in youth the 

 test is delicate, finely chitinous, and distinctly areolar in structure ; it 

 increases in thickness by the division of the areolae into two, and then 

 into several layers ; the outermost and innermost layers remain chitinous, 

 while the intermediate become charged with carbonate of lime, which 

 forms a row of globules often arranged in regular lines. The increase 

 in growth takes place throughout the whole thickness of the test, and so 

 shows that the entire envelope is living. The protoplasm, which is 

 areolated, does not always fill the whole of the test. 



From the accumulation of protoplasm round the mouth, a variable 

 number of fine transparent pseudopodia are given off; when these are 

 all retracted, there may be seen a somewhat irregular excavation, at the 

 bottom of which is the entrance to a tube, which, in appearance, is 

 analogous to the oesophageal tube of a number of Infusoria. The nuclei 



* Ber. Deutsch. Bot. Gesell., v. (1887) pp. 364-74 (1 pi.). 



t 'Die Badiolarien (Bhizopoda Badiaria). Zweiter Theil. Grundriss einer 

 allgemeinen Naturgeschichte der Badiolarien.' Folio, 1887, 248 pp. and 74 pis. 

 + Cornptes Bendns, cvi. (1888) pp. 769-71. 



