REPORT OF TEE CHIEF ASTRONOMER 811 



SESSIONAL PAPER No. 25a 



Transverse — Growth rings rather broad and well defined. Tracheids not very 

 thick-walled, gradually passing into a thin and poorly defined limiting 

 zone upwards of 8 tracheids thick. Medullary rays numerous, 1-4 cells 

 wide, resinous, distant chiefly one but sometimes three rows of vessels. 

 Vessels oval or round, more or less in radial rows, radially 1-5 seriate 

 or sometimes tangentially 2 seriate; the larger vessels occupying a zone 

 of variable width in the spring wood and often preceded by a series of 

 smaller vessels, more or less abruptly diminishing and becoming more 

 scattering toward the summer wood where they form more or less scat- 

 tering groups or finally become merged with the wood parenchyma. Wood 

 parenchyma very variable and often apparently wanting, but when pro- 

 minent surrounding groups of vessels or forming isolated and commonly 

 tangentially disposed tracts of variable size near the outer limits of the 

 growth ring. 



Radial. — Vessels short and commonly broad, the hexagonal, multiseriate pits with 

 transversely slit-like pores. Medullary rays numerous and medium to 

 rather high, the cells all of one kind though often much shortened; the 

 upper and lower walls rather thin, or in the short cells thick and 

 much pitted ; the lateral walls multiporous when contiguous to vessels. 

 Vessels of the medullary sheath spiral and scalar if orm, the adjacent 

 parenchyma filled with starch. Wood parenchyma cells about eight 

 times longer than broad. 



Tangential. — Rays of two kinds; the uniseriate rays low, inconspicuous, not numerous; 

 the multiseriate rays numerous, resinous, lenticular, upwards of 5 cells 

 wide, the terminal® not prolonged, the cells all of one kind and chiefly 

 thin-walled. 



1007 „ 



- — it- -of 1905. Exogenous wood. Undeterminable. 



1, 2a 



This number represents two fragments of wood a few centimetres square. 

 One is a separate fragment, carbonized throughout and evidently a piece of 

 exogenous wood. The other fragment, still adherent to the original matrix, is 

 about 2-3 mm. thick, fully carbonized, and showing both growth rings and 

 medullary rays. The material is too friable and too fully carbonized to make 

 sections possible. 



- — p of 1905. Phragmites, sp. 



2b, o 



Two fragmentary specimens of very imperfect leaves which cannot be 

 referred to anything more definite than Phragmites. 



1007 „ 



— of 1905. POTAMOGETON, sp. 



OC 



Among the small fragments embedded in the general matrix of specimens 

 from locality 1007, there were noticed several small, oval bodies, evidently of a 

 composite character and very suggestive of the fruit of a Carex or one of the 

 Naiadacese. Upon critical examination the conclusion was reached that they 

 belonged to the latter family, of which Potamogeton was found to be the genus 

 presenting the most favourable basis for comparison. From that point of view 

 they were found to compare closely with such species as P. mysticus, P. confer- 

 voides, P. obtusifolius, P. vaseyi, or P. diversifolius, being most directly related 

 in point of size, form and variations with P. obtusifolius. The entire absence 



