ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 40 



Balls of Vegetable Matter from Sandy Shores.*— Y\\ F. Ganong 



publishes a further contribution on this subject, and describes the com- 

 position of balls from fresh and sea water. The well-known Position ia 

 balls on the shores of the French Riviera were described as long ago as 

 1870 by Weddell, but their nature had been investigated, though never 

 publicly made known, by the botanists of Antibes. The present author 

 quotes the various literature on the subject, describing the composition 

 of balls of pine-needles, of Posidonia with or without alga? and sponge 

 remains, some of Zostera, some (in English lakes) of larch-cones, some 

 (in the lakes of the Engadine) of fir-cones and fir-needles, some (in the 

 Lake of Geneva) of wood-shavings. Recently, too, marine balls have 

 been reported from Nova Scotia, composed of alga3 — mainly Dictyosiphon, 

 Desmarestia, Ectocarpits, Ghordaria, and Chorda — with some other acces- 

 sory materials. Again, balls have been recorded from a lake in Michigan 

 composed of tamarack leaves ; and, finally, Professor Burrows, of the 

 Michigan Agricultural College, describes balls which consist almost wholly 

 of hair from a tannery located on the shore of Lake Michigan. The 

 wave-formed balls, therefore, occur in the sea as well as the lakes of 

 fresh water, and they are made up of the most diverse materials. The 

 one feature they have in common is their mode of formation, which de- 

 pends upon the rolling action of the submersed parts of waves working 

 upon fibrous substances resting lightly upon sandy bottoms. 



CRYPTOGAMS. 



Pteridophyta. 

 (By A. Gepp, M.A., F.L.S.) 



Structure of Fossil and Living Ferns.t— F. Pelourde publishes 

 the results of some comparative researches on the structure of the fossil 

 and living ferns. His conclusions are that the fibrovascular system of 

 the fronds permits four principal types of structure to be distinguished, 

 between which are found transitions often very clear. 1. The first type 

 possesses two woody bundles of Hippocampus-iovm united by their 

 extremities at various levels (Pteris cretica, Nephrodiwn molle, etc.). 

 2. In other cases, at the base of the petiole a certain number of bundles 

 are found arranged in an arc opening upwards, the upper two having a 

 xylern of triangular form with the upper point prolonged by an appendix 

 recurved within (Aspidium, Flicheia esnostensis). 3. Or again, the petiole 

 encloses a single arcuate bundle open on the upper side (living and fossil 

 Osmundaceaj). This arc is sometimes transformed into a closed outer 

 band around a transverse inner band composed of one or more bundles 

 (Matoniaceas, living and fossil Marattiacea?). 4. The vascular system of 

 the frond is composed of a solitary bundle in the form of an arc opening 

 downwards (Anachoroptcris, certain Schizrcaceas). 



Anatomy of Matonia sarmentosa.J— R. H. Compton gives an 

 account of the anatomy of Matonia sarmentosa based on material 



* Rhodora, xi. (1909) pp. 149-52. 



t Ann. Sci. Nat. Bot., ser. 9, x. (1909) pp. 115-47 (figs.). 



% New Phytologist, viii. (1909) pp. 299-310. 



Feb. 16th, 1910 e 



