,g^. NOTES AND COMMENTS. 249 



careful examination of the Sussex coast in the neighbourhood of 

 Selsea. At the base of the local Pleistocene deposits Mr. Reid has 

 discovered great boulders — some of greenstone and granite, some 

 of comparatively local rocks — squeezed into the underlying Eocene 

 clay ; and one block of Bognor Rock is recorded as showing a well- 

 marked striated surface, a feature probably produced by the agency 

 of shore-ice. Immediately above the layer of boulders, sands and 

 clays yield evidence of a temperate fauna and flora ; and above 

 these again is the " Coombe Rock " which evidently betokens 

 a return of glacial conditions. Mr. Reid, therefore, concludes that 

 there is distinct proof of an interglacial or mild episode ; and he con- 

 siders that the succession of deposits in the Thames valley may be 

 interpreted in precisely the same manner. The newer rough flint- 

 gravel and stony brickearth in the Thames valley are to be regarded, 

 in his opinion, neither as marine nor as fluviatile, but as frozen soil 

 gravels accumulated on plains gently sloping towards the river. Mr. 

 Reid further expresses his belief that the excavation of the Thames 

 valley dates back to the period of the Chalky Boulder Clay, at a 

 time when the river flowed parallel with the southern margin of the 

 ice-sheet and received its sub-glacial drainage as well as that of 

 its own catchment-basin. The conclusions thus suggested are highly 

 interesting, even if they be heterodox, and they are, at any rate, 

 calculated to stimulate enquiry. 



Recent Progress in the Study of Aloe. 



So much activity has been displayed during recent years in 

 Phycology, that the anticipation may be safely entertained of a 

 speedy journey over the remainder of the path to be traversed to the 

 point where it shall be abreast of the study of Fungi. Much of this 

 progress has been made abroad, and among recent writings, such 

 papers as those of M. Bornet on Ectocarpus {Bull. Soc. Bot. France), 

 Graf zu Solms Laubach on Cyinopolia, Neomevis, and Bovnetella {Ann. 

 Javd. Bot. Bnitenzorg), deserve mention as solid contributions to our 

 knowledge. The excellent /I ^/as dentschevMeevesalgen of Professor Reinke 

 has somewhat prematurely reached its conclusion. It now consists 

 of 50 illustrations instead of the 100 we were led to expect, and it is 

 greatly to be regretted that the encouragement offered did not 

 warrant a continued existence. As it is, our knowledge of the 

 Phaeophyceae is greatly the better of the volume. The Sylloge 

 Alganim of Dr. De Toni, proceeds without pause, though at present 

 it is travelling over the waste fields of Diatomaceae. This great 

 systematic undertaking is distinguished more for its merits as a 

 storehouse of reference than as a critical treatment of the Algae. 

 It is, in fact, anything but critical. Wille has completed his account 

 of the Chlorophyceae in Engler and Prantl's Nat. Pflanzenfamilien. 

 This account is intended as a critical review of facts, but in this 



