964 MR. F. A. POTTS ON 
the two larger individuals from Porto Praya there were 13 or 14 
respectively ; in those from St. Vincent 10 segments in most, 
9 in one or two. ‘The notopodia show differences from those 1n 
the corresponding region of M. taylori, due partly to the great 
difference in size of the two animals. In the Cape Verde species 
there is naturally a very much smaller number of setee in each 
parapodium (about 20 or 30). The setz themselves are easily 
distinguishable from those of JZ. taylori (cf. text-fig. 5) by 
their shorter heads. As in that species so here, dorsally they 
become longer and more slender, with an almost symmetrical 
Text-figure 4. 
y 
a 
—————— 
A 
A. Mesochetopterus taylori, X 70. B. Mesochetopterus minuta, X 325. 
Enlarged setze of fourth segment. 
lanceolate head. The fourth segment (text-fig. 4 B) carries ven- 
trally a number of dark brown modified setz varying from 4 to7. 
The larger ones have a distinct likeness to those of J. taylori, 
though, of course, they are much smaller. There is a tendency 
for the oblique edge of the seta to be fimbriated. This is 
apparently due, not to a natural serration, but to splitting of 
the fibrous chitin of the seta. 
The median region consists of only two segments, but it is 
nearly twice as long as the anterior region. It is the great 
likeness in the configuration of the median region which shows 
