Chap. VII. CATASETUM TRTDENTATUM, 197 



he was surprised at the gigantic seed-vessels of the 

 Monachanthiis ; and he correctly remarks that " here 

 ■\ve have traces of sexual difference in Orchideous 

 flowers." Dr. Criiger also informs me that in Trinidad 

 he never saw capsules naturally produced by the 

 flowers of this Catasetum;* nor when they were fer- 

 tilised by him with their own pollen, as was done 

 repeatedly. On the other hand, when he fertilised 

 the flowers of the Monachanfkus viridis with pollen 

 from the Catasetum, the operation never failed. The 

 Monachanthus also commonly produces fruit in a state 

 of nature. 



From what I had myself observed, I was led to 

 examine carefully the female organs of C. tridentatum, 

 calhsum, and saccatum. In no case was the stigmatic 

 surface viscid, as it is in all other Orchids (except as 

 we shall hereafter see in Cypripedium), and as is 

 indispensable for securing the pollen-masses by the 

 rupture of the caudicles. I carefully looked to this 

 point both in young and old flowers of C. tridentatum. 

 When the surface of the stigmatic chamber and of the 

 stijrmatic canal of the above-named three species is 

 scraped oft', after having been kept in spirits, it is found 

 to be composed of utriculi (including nuclei of the 

 proper shape), but not nearly so numerous as witli 

 ordinary Orchids. The utriculi cohere more together 



* Dr. Hance writes to me that often occurred. J. G. Beer says 



he has in his collection a plant of (quoted by Irmisch, ' Beitrage zu 



Catasetum tridentatum from the Biologiie der Orchideen,' 1853, p. 



West Indies bearing a tine capsule ; 22) that during three years he 



out it does not appear to have triedin vain to ftitilise Catasetum, 



been ascertuiued that this ]iar- but on one occasion, by ]ilacing 



ticular liower was that of Cata- only the viscid disc of a pollinium 



getum. and there is no great ira- within the stigma, a rij>e fruit 



l)robability in a single flower of was produced ; but it may be 



Monachanthus beiiigproduced by asked. Did the seedj contain 



^ plant c)f Catasetum, us well as a embryos? 

 wliole sciipe, which we know has 



