78 BRITISH CHAROPHYTA. 



and Edinburgh, in association with remains of Entomo- 

 straca. These may possibly be the fruits of a Charo- 

 ph}^e, but their structure is too imperfectly preserved 

 to admit of a conclusion being reached. I am indebted 

 to Dr. Kidston for the opportunity of examining them. 



As regards the MESOZOIC era, the reputed discoveries 

 of Charophyte remains in the Trias and Lias have 

 already been referred to (p. 72). 



Jurassic. — In the Bajocian stage of the Oolites 

 detached Charophyte-fruits have been found in the 

 Chipping Norton Limestone, in three of the Neaeran 

 Beds (associated with marine organisms), and in the 

 Paludina Bed, above, at Sharp's Hill (Oxon.) ; in the 

 Bathonian stage, in the Forest Marble near Tarlton 

 (Glos.), they have also been found, again in association 

 with marine organisms. Both the Bajocian and Batho- 

 nian fruits belong to several types, but these have not yet 

 been worked out, with the exception of one from the 

 Forest Marble described and figured by Mr. Upton as 

 Chara Icevigata (27). I am indebted to Messrs. Upton 

 & Walford and to the late Mr. Windoes for the 

 opportunity of examining the various gatherings. No 

 doubt the association of the fruits with marine organisms 

 is due to their having been washed out to sea. If they 

 had belonged to plants inhabiting the sea, there would 

 almost certainly be many remains of them in the 

 numerous marine formations of that period. From the 

 Oxfordian stage in the Dept. Lot, Saporta (18) described 

 and figured under the name of C. Bleicheri a small 

 Charophyte -fruit with tubercles on the spiral-cells. 

 The nature of these tubercles, which occur frequently 

 on Tertiary fossil fruits, is not at present understood. 

 In some cases they may be due to external incrustation, 

 but in others, such as those shown in Fig. 30, they seem 

 much too regular and symmetrical in outline to be 

 attributable to this cause. 



The Middle Purbeck Beds of Dorset abound in 

 Charophyte remains, and, both in point of diversity ia 



