1905.] NATURAL SCIENCES OF PHILADELPHIA. 531 



Notopodiiim and neiiropodium are each supported b}^ a stout acicu- 

 lum, both of which are nearly colorless and the former strongly curved 

 and terminating just below the base of the dorsal cirrus, the latter 

 straight and projecting rather prominently through the apex of the 

 neuropodium. 



The setse are arranged as usual in the genus (fig. 4), but in certain 

 respects resemble those of Lcetmatonice. The neuropodial setse are 

 arranged in 3 horizontal rows arising from the three steps on the end 

 of the neuropodium. The dorsal contains 1 or 2 of the stoutest, the 

 middle 2 or 3, and the ventral 3 or 4 of the smallest. While retaining 

 the same general characteristics they differ much in detail. The free 

 portion of the largest (fig. 6) exceeds the neuropodium in length, is 

 nearly straight and uniform in diameter to the distal J, which is very 

 gently curved and tapered to a point encased in a densely hairy sheath 

 terminating in a tuft of very coarse fibres with an often recurved axial 

 prolongation. The smallest ventral setse are nearly colorless, instead 

 of deep yellow like the larger ones, and much less striated longitudinally. 

 Their shafts are distinctly curved, with a short enlarged end (fig. 56) 

 tapering rather abruptly to somewhat hooked tips with less densely 

 hairy sheaths, often worn away. The middle setae (fig. 5a) are inter- 

 mediate in character. Usually 1 or 2 setse of the middle and ventral 

 series are provided with a stout curved spur at the base of the terminal 

 region. The location of such setse is so irregular and their resemblance 

 to the other setse otherwise so complete that the possibility of this spur 

 being caducous is suggested, yet this is opposed by the firmness vdih. 

 which it is fixed whenever present. 



Coarse notopodial setae are found in two tufts, one of 8 to 10 anterior 

 to the dorsal cirrus and a more dorsal one of 10 to 12. In each bundle 

 they diminish in both length and thickness from the dorsal to the ven- 

 tral margin. They are brown, polished, flattened and though stand- 

 ing nearly erect are more or less curved toward the median line. The 

 longest are 3 mm. long and, relatively to the size of the animal, very 

 stout at the base, at first gently but in the outer part rather abruptly 

 tapered to a slender end with minute superficial asperities and a hooked 

 tip (fig. 7). The smaller ones are similar but frequently taper to a point 

 lacking the hook. On the ventro-anterior aspect of the notopodium is 

 a dense spreading tuft of setse varying in size from the smallest of the 

 dorsal groups to strictly capillary fibres; all taper to capillary ends 

 which lack hooks but are provided with recurved asperities coarser than 

 those on the dorsal setae. This tuft corresponds to the lateral iridescent 

 hairs of the sea-mouse but is dull and gray in the present species. A 



