124 CALIFORNIA ACADEMY OF SCIENCES. 



BENHAMIA Michaelsen. 



The genus Benliamia was for some time considered a typical African genus, 

 and when later on a few extra-African species were found it was supposed that these 

 were recent emigrants, which had become more or less cosmopolitan. Of American 

 species two are known from Mexico and Venezuela, viz.: B. Bolavi and B. mex- 

 icana, and one, B. octonephra Rosa, has been described from Paraguay since this 

 paper was presented for publication. This latter species appears very nearly related 

 to B. rugosa, described below, but differs through the absence of penial seta;. 



The discovery of species of Benhamia at Miraflores, in the Cape Region of 

 Baja California, in a locality to which plants of any kind have rai'ely if ever been 

 introduced directly from foreign countries, would indicate that this genus has possessed 

 representatives on American soil for ages past, and that we really must consider these 

 American species as truly endemic. A final answer to this question of habitat must 

 be deferred to a future time, when more researches will have been made as regards 

 the distribution of these and other Benhamia species, as it is probable many more will 

 be found on this continent. A difficulty, which besets us from the beginning, is, that 

 so few species have been properly delineated, all descriptions having been made chiefly 

 with a view to distinguish the species from others already known, while with proper 

 delineations of the various organs, we would in all probability be able to make a satis- 

 factory comparison between species new and old. I have received much aid from 

 Dr. W. Michaelsen, of Hamburg, who has described more Benhamia species than any 

 other investigator, and who has written extensively upon this genus. He has kindly 

 placed at my disposal several species of African Benhamia, as well as of B. Bolavi, for 

 comparison with forms found by me. This has enabled me to point out several im- 

 portant differences between B. Bolavi and B. palmicola, which are sufficient to dis- 

 tinguish these as subspecies from each other, as well as from others previously known. 

 At the end of the descriptions of the various new species I append a table of charac- 

 teristics, etc., between species which may be confounded with our present ones, either 

 on account of similarity of some characters or because of their geographical distribu- 

 tion in the Malay archipelago, or in America. 



As we now understand the distribution of this genus, the species are divided as 

 follows: America, 7 species; Malay archipelago, 3 species; Africa, 25 species; West 

 Indies, 2 species. 



It may, however, be remarked that B. myosin described below is of uncertain 

 habitat having only been found in a hot-house, to which it had been imported from 

 unknown country. 



Considering our various new species of Benhamia this genus may be charac- 

 terized as below: 



Benhamia Michaelsen. 



Acanthodrilid oligochteta. Set* strictly paired, ventral and lateral. Cli- 

 tellum generally incomplete, but in .some species complete in .some somites. Two 

 gizzards in succeeding somites. Calciferous glands generally three pairs, but some- 

 times only two pairs, very distinctly set off from the tubular intestine. Nephridia in 



