MERRILL! SYSTEMATIC POSITION OF THE "RAIN TREE" 45 



precedes the generic diagnosis. Following the generic diagnosis 

 are cited Inga excelsa Kunth, /. unguis cati Willd., /. bigemina 

 Willd., /. cyclocarpa Willd., I. cochleata Willd., and I. contorta 

 Willd., and the original descriptions of P. auaremotemo Mart., 

 P. cauliflorum Mart., and P. gummiferum Mart. Of the ten 

 species mentioned or described six are now placed in Pithecolo- 

 bium, three in Enterolobium, and one in Inga. 



I have merely stated the case for and against two possible in- 

 terpretations of the type of the genus Pithecolobium. Conveni- 

 ence will certainly be served much better by the selection of P. 

 unguis cati as the type. With this introductory statement re- 

 garding the genus Pithecolobium itself it is now proposed to con- 

 sider a single species, long placed in the genus, but which the 

 author considers to be generically distinct. 



In the year 1800 the species under consideration was originally 

 described by Jacquin from South American material as Mimosa 

 Saman. It was transferred to Inga by Willdenow a few years 

 later and subsequently by other authors successively to Pithe- 

 colobium, Calliandra, Albizzia, and Enterolobium. Thus m less 

 than one hundred years it has been considered by different 

 writers under six generic names. As the various genera are now 

 interpreted, Pithecolobium Saman, to use its generally accepted 

 name, differs radically from all. Mimosa, Inga, Calliandra, and 

 Albizzia can be dismissed without discussion, as the rain tree can- 

 not possibly be referred to any of these genera. As between the 

 two remaining genera, Pithecolobium and Enterolobium, it can- 

 not possibly belong to the former as it has somewhat fleshy, at 

 least pulpy, straight, indehiscent, and septate pods. Its true 

 alliance is unquestionably with Enterolobium, where Sir David 

 Prain has placed it; and yet in its straight or nearly straight, 

 fleshy or pulpy pods and pedicelled flowers it is decidedly anom- 

 alous in Enterolobium, while in facies it is very strikingly dif- 

 ferent from the representatives of this genus known to me. 

 Prain's 8 discussion is so lucid and to the point that it is here 

 reproduced : 



When Mr. Bentham tentatively placed the species [Enterolobium 

 saman Prain] in Pithecolobium he explained that the tree was unknown 



* Journ. As. Soc. Beng. 64 2 : 252. 1898. 



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