i 3 8 SCIENCE PROGRESS 



among previously described Carboniferous fossils, and /socles, 

 among recent Lycopods. 



From the Lower Carboniferous rocks, a new Lepidodcndron 

 (L. petty curense) has been described by Kidston (34), the structure 

 of which is interesting from the fact that the stem possesses 

 not only a well-developed zone of secondary wood but a solid 

 central mass of primary wood. 



A new Lepidophloios (L. Scottii) in the Halonial condition, has 

 been discussed by Mr. W. T. Gordon of Cambridge (20). Here 

 the external surface of the stem was exposed and its characters 

 were found to differ from the typical Calciferous Sandstone 

 member of this genus, L. scoticus, well known from impressions. 



From the Upper Carboniferous rocks, the correlation of 

 the external features of two species of Lepidodcndron, occurring 

 very commonly as impressions, with their internal structure, 

 has proved interesting and important. Both in the case of 

 L. obovatum elucidated by Scott (51), and in L. acideatum soon 

 afterwards discussed by Seward (56), the type of internal 

 structure proved to be that hitherto associated with the genus 

 Lepidophloios alone. Thus we know now that the so-called Lepido- 

 phloios type of anatomy was common not only to the genus 

 Lepidophloios, but also to some, though not to all, species of 

 Lepidodcndron. 



The stems and branches of another species, L. sclaginoides, 

 have also been correlated from structure specimens by Weiss 

 and Lomax (72) by means of actual continuity between the two 

 organs. 



Weiss (70) has contributed a special study of the parichnos 

 in the Lepidodendraceae, the function of which he regards as 

 respiratory. Watson (66) has described a new species of 

 Lepidodcndron (L. Hickii) in the Halonial state, formerly con- 

 fused with L. Harcourtii. 



The latter author (68) has also published a memoir " On 

 the Ulodendroid scar," which he regards as " the place of 

 insertion of an ordinary branch, which was probably provided 

 with some sort of branch-shedding mechanism," not, as has 

 hitherto been supposed, the scar " produced by the pressure 

 of the base of a sessile cone." 



An important contribution to our knowledge of Bothro- 

 dendron has been made by Watson (67), who has attributed 

 to this genus a heterosporous cone of small size, conforming 



