24 Mitchell.—Contributions towards a Knowledge of the 
strobilus itself was originally produced. The occurrence of sporangia in the 
sterile region is very rare, only one case (S. molliceps) having come under 
my notice. The sporangium was, of course, abortive, but was situated 
in the axil of one of the large stem leaves, at a distance of quite three 
inches from the cone. Remains of one abortive megaspore could be seen. 
Pltirality of Sporangia. 
Miss Lyon (8) has recorded a case of two megasporangia in the axil of 
one leaf in 6*. rupestris , one situated in the normal position, and the other 
in the line joining this one to the base of the ligule. Bower ( 2 ), on examin¬ 
ing Lycopodium rigidum , discovered a similar case, the two sporangia, 
however, lying side by side, and arising probably ‘ by the separation of the 
sporogenous group of a normal sporangium \ 
In 5 . I^yallii I found a further anomalous condition. The two 
sporangia (which were found on a leaf quite at the tip of the cone) were 
widely removed from each other ; one was perfectly normal in character, but 
the stalk of the other occupied the position of the glossopodium of the 
ligule (PI. IV, Figs. 1,2). The interpolated sporangium had taken the place 
of the lamina of the ligule, or possibly the lamina of the ligule had changed 
into a sporangium. I have not met with any other case of a double 
sporangium either in 5 . Lyallii or in any other species. If the cases cited 
above be regarded as merely sports, Bower’s statement (2) that ‘ the inter¬ 
polation of accessory sporangia is entirely absent in the Lycopods ’ is quite 
supported by the Selaginellaceae. 
The variation in the number of spores in the sporangium. 
The number of spores in the microsporangium is indefinite, but always 
exceedingly large ; the megasporangium contains typically four, and 
frequently remains of the degenerate spore mother-cells may be seen. 
Besides the cases described by Miss Lyon (6) in 5 . apus and 5 . rupestris , 
reductions take place in the following species also, and are classified accord¬ 
ing to the character of the reduction. 
1. Inequality of size of spores. 
S. Vogelii, 
S. rubella , 
5 . Kraussiana , 
vS. Lyallii , 
.S. Braunii , 
vS. rupestris , 
2 cases 
1 case 
2 cases 
1 case 
1 case 
2 small, 2 large. 
)) 
a 
3 large, 1 small. 
3 » 1 
2 „ a 
if 
it 
several cases. 
2. Reduction to three equal megaspores. 
S. cuspidata (2 cases), S. molliceps (2 cases), S. Kraussiana (1 case), 
5 . Braunii (1 case), 5 . oregana (2 cases). In 5 . Bakeriana there are 
normally three megaspores. This is so constant a feature that the 
