ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 467 



studied in five species, and their characters are summed up in a synop- 

 tical form. The author gives a list of other species which require further 

 investigation. Finally the author states that although the chains of 

 Melosira islandica and of M. italica exhibit a pleomorphism of the indi- 

 viduals, yet after the formation of auxospores the species reverts to its 

 normal form. The purport of the pleomorphism is not yet understood. 

 • 



New Coralline Algae. — M. Foslie * describes some new species and 

 varieties of Lithothamnion and Lithopliyllum, mostly from the Antarctic 

 region, collected by the ' Gauss,' the ' Discovery,' the ' Antarctic ' and 

 the ' Scotia.' Species from Port Phillip and the West Indies are added. 



Another paper f gives further descriptions of new species and of a 

 new genus, Lithol&pis, which is intermediate between Melobesia and 

 Mastophora. Litholepis contains three species, L. {Melobesia) caspica 

 and L. {Melobesia) bermudensis already described, and a new species, 

 L. Sauvageaui. Notes follow on Goniolithon, Heteroderma, and Der- 

 matoliihon. 



A number of dead nodules of Lithothamnion were brought up by 

 excavators in the harbour of Vardo in East Finmark, and these are 

 described by the same author % as a new species, L. Vardoense, approach- 

 ing in habit L. norvegicum f. nodulosa. Living specimens of Litho- 

 thamnion are no longer found in the harbour. 



Seven new species and three varieties from the West Indies are 

 described and figured by M. Foslie and M. A. Howe.§ Some of these 

 are sterile, but the plants possess well marked distinctive characters in 

 outward form or internal structure. 



Finally, in a short paper eighteen new species and some varieties are 

 described by M. Foslie || from various parts of the world. 



Remarks on Northern Lithothamnia.lf — M. Foslie publishes a 

 detailed account of the Norwegian species of Lithothaninioneae and 

 Melobesiese. The paper opens with some interesting observations on 

 the group, in which the author gives his reasons for the reduction of 

 species and the formation of new forms. He considers that Litho- 

 thamnia are largely influenced by outside conditions, and that plants 

 which have been made types of new species are in reality but peculiar 

 forms of existing species. There are three principal agents which mili- 

 tate against normal development in this group : (1) larger Crustacea 

 and boring mussels which break and otherwise damage the plants ; 

 (2) boring algae, especially Ostreobium QueJcetti Born, and Flah. ; (8) 

 friction from strong currents, reducing branched plants to compressed 

 globular masses. Lithothamnia flourish best where there is a firm 

 bottom and the tidal action is fairly strong, without being excessive. 

 Full descriptions are given of species and forms, with their respective 

 synonymy, followed by copious critical notes. 



» Kgl. Norsk. Vidensk. Selsk. Aarsb., 1904, 4 pp. 



t Op. cit., Skrift, 1905, No. 5, 9 pp. J Tom. cit., No. 2, 4 pp. 



§ Bull. New York Bot. Gard., iv. (1906) pp. 128-36 (14 pis.). 

 || Kgl. Norsk. Vidensk. Selsk. Aarsb., 1905, 8 pp. 

 If Op. cit., Skrift, 1905, No. 3, 138 pp. 



