Doyle — Observations on the Morphology of Larix leptolepis. 311 



foliage leaves; but a definite bare length of pedicel intervenes between these 

 and the lowest microsporophylls. This characteristic is in marked contrast 

 to the female strobilus. "But, apart from this, two facts appear of interest. 



A. Cavities in the Sporophyll. — In a longitudinal section of a mierosporo- 

 phyll the terminal lamina is quite large and distinct, and is occupied by a 

 conspicuous cavity. Text fig. 1 shows an outline drawing of the arrange- 

 ment. It is worthy of note that the cavity is limited to the lamina, and that 

 in the bud stage this cavity is especially noticeable. PL XVII, fig. 1, shows a 

 longitudinal section of a mature winter male bud, the cavity in this stage 

 appearing very well in the lowest sporophyll. 



PI. XVII, fig. 2, is a transverse section of a similar bud from which 

 we learn that the cavity is really a double cavity which may become, and 

 during growth usually does become single as a result of fusion. The struc- 



Fig. 1. — Longitudinal section of microsporophyll of Larix leptolepis, showing relatively 

 large " knob " and marked cavity in it even at full maturity, x 50. 



tures marked A are the apical knobs of the next lowest sporophylls. Special 

 attention is directed to those actually labelled A. Both figures make it 

 evident that the cavities are not in communication with the cortical canals 

 of the cone pedicel. 



Now, Coulter and Land (4) have maintained for Pinus laricio that the 

 two small cavities in the microsporophyll apex are possibly abortive sporangia, 

 Taxits, Torreya, and Pinus thus representing a series in degeneration from a 

 primitive peltate type. Miss Starr (23) makes a similar claim for Ginkgo. 

 Although a primitive peltate stamen of a " sporangiophoric " type has much 

 to recommend it in theory, we find certain points in the structure of Larix 

 that certainly seem to oppose it in fact. 



Thus, turning to PI. XVII, fig. 3, we see a transverse section of a vegetative 



bud of Larix leptolepis, in which the two canals so common in the conifer leaf 



3e 2 



