ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 729 



Silurian of Bowning and Yass. The specimens are undoubted examples 

 of a Monograptus, apparently belonging to the group typified by M. 

 dubius, which ranges through almost the whole of the Lower Ludlow 

 and Wenlock in Britain. 



Development of G-raptolites.* — E. Kerforne has found among the 

 Graptolites of the Armorican " massif " of Brittany a number of de- 

 velopmental stages of Monograptus convolutus His, showing the " float " 

 attached to the rhabdosome, numerous siculge with the first hydrotheca, 

 and so on. 



The Genus Romingeria.| — Charles E. Beecher gives an account of 

 the structure and habits of four characteristic species of the genus 

 Romingeria, in which some details not hitherto observed are noted. 

 He reviews the history and synonymy of the type species, R. umbellifera r 

 and briefly refers to possible affinities with other genera of palaeozoic 

 tabulate corals, e.g. Pleurodictyum and Favosites. 



Porifera. 



Asterosteptidse.l — E. Topsent discusses this new family of Choristid 

 sponges, which ranks along with Gray's Geodidae and Sollas's Stellettidse 

 in the tribe Astrophora. The proposed new family includes the Theneinte 

 and Pachastrellidse as sub-families. 



Insufficiently Described Monaxonia. § — Joh. Thiele has revised 

 twenty-seven species of Monaxonial sponges which Schmidt ,did not 

 adequately describe. He has made use of the original types, or of 

 sections which Prof. Weltner had previously made of many. And after 

 filling up some of the many gaps in the descriptions, he shows what 

 changes in nomenclature are necessary. 



Calcareous Sponges from the Pacific. || — Josef Preswisch de- 

 scribes two new species of Leucetta, two of Sycandra, and one of 

 Ebnerella, collected by Schauinsland from Chatham Islands," Laysan, 

 &c. The collection also included the two cosmopolitan species, Ascetta 

 primordialis and Sycandra coronata. 



Pacific Horny Sponges.1T — R. Baar describes a collection of thirty- 

 six specimens collected by Schauinsland from the Pacific. The collection 

 included five genera and thirteen species, and Stelospongia flava is 

 established as a new species. 



Protozoa. 



Sexual Reproduction of Pterocephalus.**— L. Leger and 0. Duboscq 

 have studied the highly specialised anisogamous conjugation of very 

 minute rod-like spermatozoa with large ovoid ova, well-equipped with 



* Trav. Sci. Univ. Rennes,i.(1902) pp. 187-90 (9 figs.), 

 t Amer. Joum. of Sci., xvi. No. 91 (July 1903) pp. 1-11, pie. 1-5. 

 \ Trav. Sci. Univ. Rennes, i. (1902) pp. 317-31. 

 § Archiv. Naturges., lxix. (1903) pp. 375-98 (1 pi.). 

 || Zool. Jahrb. xix. Heft.i. (190:5) pp. 9-26 (3 pis.). 

 f Tom. cit, pp. 27-36 (3 figs.). 



** Arch. Zool. Exper., I. series 4 (1903). Notes et Revue, No. 9, pp. cxh.-viu 

 (11 figs.). 



