316 PROCEEDINGS OF THE ACADEMY OP [1886. 



Cassia Marilandica, and I having a good opportunity for daily- 

 observation, I undertooli its close investigation this year. In 

 Cassia Marilandica the flower consists of five petals, as in other 

 leguminosae; but the two which usually unite and form the carina 

 are here distinct and spread widel}^, talking the place apparently 

 often occupied by the wing-petals. The two actual wing-petals 

 are somewliat erect and lap under the upper or vexilliim. This 

 arrangement gives the flower a "somewhat two-lipped appear- 

 ance." The style curves gradually, but more rapidly at the apex, 

 curving there so much that the stigmatic surface can scarcely be 

 closely examined without breaking the style. If the petals be 

 opened just before the natural time for their expansion, a globule 

 of liquid is pendant from the surface. Tlie stamens are arranged 

 in separate sets. Tliere are three beneath the pistil the two 

 lateral ones are very strong and equal the pistil in length the 

 central one immediately beneath the pistil is as long as those on 

 each side, but more slender. Immediately above tlie pistil are 

 four stamens, with short, stout filaments, the anthers being per- 

 fectly formed, and nearly as long as in the lower set. Above are 

 three petaloid stamens, which we can only see are staminal efforts, 

 by noting the intermediate stages of the several parts between 

 the stamens and petals. The only use for them seems to be to 

 afi'ord a good morphological lesson to the student. 



The most interesting feature of this Cassia is that the stamens, 

 not mono or diadelphous as in manj- leguminosae, have long, 

 black anthers, full of pollen, but which seem never to burst the 

 anther cases. The only " opening is at the apex," and this " open- 

 ing " is covered by a membrane never opening, as I believe, 

 except by insect agency. 



As soon as the flower expands it is freel}^ visited by humble 

 bees, and, as their loaded thighs evidence, for the pollen. To 

 collect this, they alight on the anthers of the long and lower 

 stamens, as on a platform make an opening in the apex of each 

 of the four shorter ones, and then rifle them of their contents. I 

 watched a mass of plants containing eight3'-eight flower stems, on 

 the 30th of July, and the same lot for an hour on 6th of August, 

 but saw no attempt to get pollen from the longer anthers, or to 

 use them in any way but as a platform. It would, indeed, be 

 hardly possible for the bee to stand anywhere so as to get power 

 to pierce the apical membranes of the longer stamens. When the 



