THE FRUIT OF TROPIDOCARPUM. 117 



One feature of the TropidocarpiLm fruit remains to be 

 noted, namely the pubescence. The pods of the gracile type 

 are usually hispid with short reflexed hairs (although rarely 

 smoothish) but this pubescence disappears about in propor- 

 tion to the divergence of form from the gracile type. We 

 cannot, however, lay much stress upon this character. If the 

 changes in the form of the capsules are in reality due to ter- 

 atogenic influence, the gradual loss of pubescence may result 

 from the same unknown cause. Loss of pubescence in de- 

 formed structures is, we believe, by no means rare. It is 

 impossible yet to say just what part teratology plays in the 

 modification of the Tropidocarpum capsules, and opinions on 

 this point may differ widely, yet it is certain, from the facts 

 at hand, that any systematic treatment of the genus, which 

 wholly neglects this erratic element in variation, is not likely 

 to give us the " still much needed " critical revision of the 

 species. 



EXPLANATION OF PLATE. 



Fig. 1. Capsule of T. gracile, Hook., from specimens in 

 Herb. Gray, collected at Antioch, Calif, by Mrs. T. S. Bran- 

 degee. 



Fig. 2. Capsule of the " dubium type," from specimens 

 in Herb. Gray, collected at Los Angeles, by J. C. Nevin. a. 

 Point of change in the valves. 6. Edge of the replum. c. 

 Mid-rib of the valves. 



Fig. 3. Replum and septum of T. gracile^ Hook, from 

 specimens in Herb. Calif. Acad., collected at Bitterwater, by 

 Miss Alice Eastwood. 



Fig. 4. Replum and partial septum of a pod of the 

 " dubium-type," secured at the same place and by the same 

 collector, a. Narrow septum in the upper obcompressed 

 portion of the capsule. 6. Column of the replum in the 

 lower unicellular laterally compressed portion. 



Fig. 5. Four-valved capsule of T. capparideum, Greene 

 from specimens in Herb. Gray, collected at Lathrop, Calif., 

 by J. G. Lemmon. 



