88 PEOCBEDINGS OJF THE 



In external morphology the resemblance was closest with the 

 Equisetales. 



The anatomy of Sphenophyllum ^¥as then illustrated ; the 

 centi'ipetal, triarch or hexarch primary wood, and the successive 

 addition of secondary tissues by means of a normal cambium, were 

 among the chief points noted, the formation of a regular scale-bark 

 being another remarkable feature. 



The cones were next described, that of Splienophyllum Dawsoni, 

 identified by M. Zeiller with S. cuneifoUum, being explained in 

 detail. The presence oi pedicellate sporangia, of peculiar structure, 

 appeared to be general in the genus, and there were reasons for 

 regarding the pedicel as comparable to a ventral lobe of the sub- 

 tending bract. 



The question of heterospory was discussed, and the evidence 

 regarded as wholly inconclusive. 



Bowmanites Hoemeri and Splienophyllum Tnajus were cited as 

 examples of somewhat more comj^lex forms of Sphenophyllaceous 

 fructification. The latter was compared with the fructification 

 of Tmesipteris, and the points of agreement between Psiloteae and 

 Sphenophyllales indicated. 



Cheirostrobus petty cur ensis, a cone discovered some years ago in 

 the Lower Carboniferous strata of Burntisland, was described, and its 

 highly complex organization explained. The agreement anatomi- 

 cally with the Lycopods and morphologically with the Equisetales 

 was found to be even more striking in Cheirostrobus than in the 

 Sphenophyllese proper, and the reasons were given which have 

 led the author to place the genus in the Class Sphenophyllales. 



The various views which have been held as to the affinities of 

 the Sphenophyllales were then discussed in the light of the results 

 recently attained. The supposed relation to Hydropterideae, 

 though supported by some ingenious arguments, was rejected as 

 baseless, and as inconsistent with the manifest Filicinean affinities 

 of that family. 



The author came to the conclusion that the Sphenophyllales 

 were most naturally regarded as the derivatives of a synthetic 

 group, combining the characters of Lycopods and Equisetales, and 

 indicating the common origin of those two Classes. 



IV. Copy of a Letter addressed to the Secretary of State for the 

 Colonies, alluding to Dr. Griinther's Presidential Address, on 

 the 24th May, 1898 (Proc. Linn. Soc. 1897-98, pp. 25-26). 



Government House, Sevcbelles, 

 10th March, 1899. 

 SlE, 



I have the honour to acknowledge the receipt of your 

 despatch No. 86 of the 16th December last enclosing two copies 



