1042 SUMMARY OP CURRENT RESEARCHES RELATING TO 



filter. The microspores must therefore be sufficiently minute to pass 

 through the paper. 



Navicula Durrandii n. sp. F. K. — Mr. F. Kitton gives the 

 following specific description of this new diatom. " Valve elliptical- 

 lanceolate, apices produced, median blank space linear-elliptical 

 with two narrow lines of puncta one each side of the raphe, markings 

 composed of longitudinal lines (about 8 in • 001 in.) of puncta 

 24-28 in -001 in. Length, •0116--0200 in.; breadth, -0038- 

 • 0040 in. Habitat, Island of Rea, near Singapore. I am indebted 

 te Mr. A. Durrand for this beautiful species ; it occurs sparingly in 

 a dredging recently made by him in the above-mentioned locality, 

 and from which he has permitted me to make some preparations. 

 Although apparently a robust species, it is really not so, as the some- 

 what numerous fragments of valves unfortunately testify. In almost 

 every case the fracture occurs between the longitudinal lines. An 

 examination with a power of 750 diameters shows that these lines are 

 dentate elevations, and the spaces between them concave grooves. 

 Under a lower power (40 diameters) the valve is slightly iridescent, 

 but the lines are visible. I have named this fine form after Mr. 

 Durrand." 



Fossil Marine Diatoms.* — Prof. P. T. Cleve describes the fossil 

 diatoms found recently in the marine deposits of Moravia, known as 

 Tegel (marl or clay) belonging to the miocene and pliocene divisions 

 of the tertiary formation. 



The new species are Campylodiscus ohsoletus, Triceratium turgidum, 

 AulacodtscMS Grunowii, Auliscus jpulvinatus, Podosira antediluviana, 

 Syringidium sp., Melosira Omma, Goscinodiscus T/mmii, and Aulaco- 

 discus sp. (found by Mr. F. Kitton). A new family, Thaumatodisci, 

 is established to include some very remarkable forms, the valves of 

 which have prominent central processes. Prof. Cleve places in this 

 family Thaumatonema Grreville, Strangidonema Greville, and Pyrgo- 

 discus n. gen., P. armatus n. sp. 



Some eighty species have been found in the Tegel, with two 

 exceptions all marine. Only a comparatively few appear to be extinct, 

 and of these a remarkable number have been detected in the Moron 

 deposit said to be found near Seville. Of the recent species many 

 forms are now living in the seas of Japan, California, West Indies, &c., 

 proving that the Tegel was a deposit in a tropical or subtropical sea. 

 It is of interest to compare these fossil forms with recent specimens, 

 and to note how little their characteristics have been altered during 

 the long period since the later tertiary. 



liiclieues. 



Miiller's ' Contributions to Lichenology.'t — Dr. J. Miiller con- 

 cludes his ' Lichenologische Beitrage,' which have been going through 

 twenty- one numbers of ' Flora,' with some general remarks. 



* Journ, Quek. Micr. Club, ii. (1885) pp. 165-77 (2 pis.), 

 t Flora, Ixviii. (1885) pp. 345-56. 



