J 58 Palaeontologie. 



I. Calamopitys Unger. 



1. Calamopitys fascicularls. Two specimens were examined; 

 one, lent by Mr. R. Kidston, is from rocks of the Calci- 

 ferous Sandstone series, in the Kilpatrick Hills (Southern 

 Scotland); the other, in the Williamson Collection, is 

 from the Carboniferous Limestone, near Haltwhistle, in 

 Cumberland. The chief results of the investigation are as 

 follows: 



1. The small pith (2 — 3 mm. in diameter) is surrounded 

 by a ring of distinct primary Strands of xylem, 8 or 9 

 in number. The spiral elements of the protoxylem 

 occur about in the middle of each xylem-strand, which 

 is thus mesarch in structure, as in Lyginodendron. 



2. The primary xylem-strands pass out through the se- 

 condary wood, and form part of the leaf-trace bundles. 

 They attain their maximum diameter (0.8 — 1 mm) at their 

 point of exit from the pith. Below this point they 

 rapidly diminish in size, and each Strand unites with 

 its neighbour on the kathodic side. 



3. The outgoing Strands are arranged according to a 2/5 

 phyllotaxis. Each leaf-trace, where it traverses the wood, 

 is represented by a Single Strand. 



4. The secondary wood has the typical Araucarian or 

 Cordaitean structure, with medullary rays one, or at 

 most two, cells in thickness. The inner part of the 

 secondary wood consists of short broad tracheides, which 

 may have served for water-storage. 



2. Calamopitys beinertiana. The specimen investigated is 

 from Norham Bridge, on the Tweed, and the horizon is 

 that of the Calciferous Sandstones. The sections are in 

 the collection of Mr. Kids ton, who identified the fossil 

 with the Araucarites beinertianus of Goeppert, an identi- 

 fication confirmed by comparison with authentic sections 

 of that species, kindly lent by Count S ol m s- La üb ach. 



The chief points in the structure may be thus 

 summarized : 



1. Around the large pith (13 — 15 mm. in diameter), which 

 contains „sclerotic nests" as in Lyginodendron, numerous 

 primary xylem-strands are present. 



2. These Strands resemble those of C. fascicularis, except 

 in their larger number, and in the fact that their 

 structure becomes endarch in the lower part of their 

 course. 



3. The secondary wood has Cordaitean structure, with 

 medullary rays rarely more than one cell thick. 



4. A scale-bark was formed on the old stem. 



The two species, C. fascicularis and C. beinertiana, are 

 placed in Unger 's genus Calamopitys (unfortunately named, 

 as it has nothing to do with Calamarieae) on the ground of 



