1901.J OF THE GENUS BENHAMIA, 207 



value by this variation in position. Foi' example, in Benhamia 

 crassa the pores lie in front, though also slightly to the inside, of 

 the ventralmost seta. 



The clitellum extends from segments xiii.-xx. and'leaves only the 

 area which is occupied by the male pores free. The latter lie upon 

 the segments which they universally occupy in this genus. The 

 seminal groove which connects the two successive pores of each 

 side of the body is quite straight. 



The internal anatomy is like that of the genus, and only shows 

 some slight differences from other species. Tlie sejyta Avhich divide 

 segments x./xiv., i. e. four septa, ai'e specially thickened. 



The gizzards occupy segments v. & vi. The calciferols glands 

 are in segments xv., xvi., xvii. The glands are bean-shaped, and 

 the upper surface is traversed by a few longitudinal furrows, 

 which divide the glands into segments. 



The last pair of hearts are in the twelfth segment, and the dorsal 

 vessel is throughout a single tube. 



The S])erm-sacs are in the same segments as those of the last 

 species described, i. e. xi. & xii. They are large and racemose. 

 There is no doubt that this species, like at any rate some others, 

 has sperm-reservoirs also which enwrap the funnels and testes. I 

 cannot attempt an accurate description of them, but can assert 

 that a pair project forwards, just as these pouches generally do 

 when they are present, into the xth segment. 



The spermiducal glands are fairly long and coiled ; I occasionally 

 observed the posterior pair to be the smaller. The muscular ter- 

 minal duct is longish. The glands lie in two segments. The shape 

 of the j^>eu?a? setcn of this species is quite peculiar for the genus, 

 and would serve at once to distinguish it, if there were no other 

 characteristics. One of the setae is shown in the drawing exhibited 

 (text-fig. 17, p. 208). Its shape is, as will be seen, straight in the 

 shaft like tliat of the other East- African species already dealt with 

 here. The end imbedded in the body-wall is curved slightly and 

 thicker. The opposite extremity of the seta is also curved and in 

 the same direction : it does not end in a very fine point but 

 diminishes gradually and not very much in width. The termination 

 is therefore a blunt point. It is the ornamentation of the genital 

 seta which is so characteristic. This consists of two rows of 

 spines which commence about half-way down the seta or a little 

 less. They appear to be much like the penial setse of Stidihnannia 

 variabilis ^ figured by Michaelsen. In two setae which I examined 

 I found slight differences in the arrangement of these spinelets ; 

 in one which I have selected for figuring the two rows ran to the 

 end of the seta, and between them not far from their origin are 

 indications of a third row consisting of two separated tracts of 

 spinelets. In another example this middle row ran to the end of 

 the seta, and the lateral row of one side ceased a little way from 



' " Bescbreibung der von Herrn Dr. Fr. Stublraann auf Sansibar, &c." JB. 

 Hamb. wiss. Anst. ix. 1891, pi. ii. fig. 12. 



