340 SUMMAEY OF CUEEENT EESEAECHES EELATING TO 



Fresh-water Algae in Kew Gardens.* — F. E. Fritsch writes an 

 account of the fresh-water algal flora of Kew Gardens. He divides it 

 into three groups : (1) the greenhouse flora ; (2) the Thames flora, con- 

 sisting of the algas in the artificial waters and the tanks in the green- 

 houses ; (3) the terrestrial flora, made up of species growing on damp 

 ground, rocks and trees in the open air. The total number of genera 

 recorded is 130, and the number of species is 294, of which the Cyano- 

 phyceas constitute nearly 25 per cent. In the aquatic tank near the 

 Jodrell Laboratory, a regular sequence of algal forms was observed, and 

 this is shown in a table. The plankton of the artificial waters at Kew 

 is, in its general character, almost the same as that of the Thames, 

 though in quantity of individuals it is very different. There is an entire 

 absence of Peridineas in the Kew flora. A list of species is given, with 

 the locality of each. 



Bacillariae from Texas and New Mexico.f — A. M. Edwards de- 

 scribes fossil diatoms from the Staked Plain, which includes part of 

 Texas and part of New Mexico. He gives a description of the district 

 with its boundary limits, followed by a list of the 67 diatoms recorded 

 from there ; notes are given on many of the species, as well as on the 

 geology of the district. 



Diatoms from near Lake Chad.J — P. Petit and H. Courtet issue a 

 preliminary note on the diatoms observed in sundry geological specimens 

 collected by the Chari-Lac Tchad expedition. Diatoms have been found 

 which, though fossil, are of a recent age, since they are represented in 

 fresh-water at the present day. The deposits in question are from 

 Ardebe and Mondo. At the former place the genera Gomphonema, 

 Cymbella, and Epithemia are the most common, and the following species 

 occur : Cymbella cucumis, Navicula obtusa var. lata, Navicula cequa- 

 torialis, and Eunotia gibbosa. The calcareous deposit in which they 

 were found is at a depth of 40 metres. In the calcareous tufa of Mondo 

 were found large numbers of Cymbellae, as well as specimens of Stephano- 

 discus astrcea Ehrb., and Surirella arcta A. S., which is very abundant. 

 This species has only been found hitherto in the Demerara river, where 

 it is living. The tripoli of Mondo is almost entirely formed of common 

 species of Gyclotella, Gaillonnella, and Cymbella. 



Yorkshire Diatoms.§ — E. H. Philip publishes the records of diatoms 

 collected on two excursions by the Yorkshire Naturalists' Union in 1905. 

 The localities were the Givendale Springs and the Ousethorpe Brook 

 near Pocklington, and Maltby. The most interesting find was a variety 

 of Fragillaria capucina, not hitherto described. Instead of the constric- 

 tion in the median portion of the valve, characteristic of var. mesolepta, 

 there is in the new variety a distinct dilatation. 



Sargassum filipendula.|| — E. B. Simons has made a morphological 

 study of this species, and presents her results under the headings of : 



* Kew Bull., add ser. v. (1906) pp. 187-220. 



t Nuov. Not., xvii. (1906) pp. 61-9. 



X Cornptes Eendus, cxlii. (1906) pp. 668-9. 



§ Naturalist, Jan. 1906, pp. 14-15 (figs, in text). 



U Bot. Gazette, xli. (1906) pp. 161-82 (2 pis.). 



