ON A NEW SI'KCIES OF SCLEROCHEILVS. 301 



The armature of the second notopodium and neuropodium is composed of 



two series of capillary eh;i>t;r. of about ten ami forty re-peel i\ ely. similar to lint 

 rather longer than those in the first neuropodinm. The ch;et,-e of tin- anterior 

 ro\v are proportionately longer, and hence there is less difference in length between 

 them and the ch;rta- of tin- posterior ro\v. In several of the specimens examined 

 there are in the second notopodiuni or neuropodium, or in both, two, three, or four 

 furcate chaetae, but these are neither so large nor so well formed in regard to their 

 prongs as those found in the following segments. They are very fragile, and 

 perhaps this explains \vliv they are not seen in preparations of the second parapodinm 

 in all cases. 



In the notopodiuni and neuropodium of the third and following segments the 

 capillary chteta? are similar to those of the second parapodium, lint in addition there 

 is an anterior series of furcate chsetse the prongs* of which agree almost exactly 

 in size and proportions with those shown in text-tig. 2 (p. 29G), but the shafts are 

 rather shorter. 



The parapodia of N. mi until* are very similar to those of the Scotia Bay 

 specimen; the figure of one of the latter (fig. <>) would serve equally well for a 

 parapodium from about the 36th segment of N. minutus, except that the latter is 

 smaller (about three-fourths the size shown). 



SAINT-JOSEPH states that behind the 22nd segment the parapodia. bear nenro- 

 podial cirri, and u similar statement is made by Professor M'lxxosH and by 

 .M. and Mme. DEHORNE. I have, examined fifteen well-preserved specimens from 

 different localities the Adriatic-, Saint-Vaast, Plymouth, and the west coast of 

 Ireland and find that the most anterior neuropodial cirrus is situated on the 25th, 

 _'7th. 2Uth, or 31st chsetiferous segment in the various .specimens. Of five specimen- 

 from the Adriatic (collected by GRUBE) in which the neurocirri are preserved, three 

 bear minute cirri on the 2.~>th segment ; in the other two the first neurocirri are on 

 the 27th segment. Of the four specimen- from Saint-Yaast, two have the first 

 neuroeirrus on the 27th segment, the other two on the : I st segment. The specimen 

 from Plymouth presents its first neuroeirrus on the 27th segment. Of the five 

 specimens from the west coast of Ireland, two have the first neuroeirrus on the 2!)th 

 segment, and three on the :!|st. In <!I;VJBE'S figure t of N. minutus the first neuro- 

 eirrus is shown on the :'.()th ehsetiferons segment. As (!IU:I:K^ remarked, the cirri are 

 not respiratory structures, for blood does not enter them. They are purely sensory, 

 as the presence upon them of sense-hairs indicate.-, and are composed of epidermal 

 cells surrounding a thin axial strand, formed apparently of nerve fibrils. 



>ne of the neuropodia examined, from a specimen IV 1'dack-od Bay. Co. -Mayo, 



* In a neuropodium from one nf the specimens from Blacksod Hay, Co. Mayo, Ireland, there occurs a fun-ate 

 rh;i'ta with an additional (third) prong, arising from between the bases of the I wo normal ones. This prong is shortrr 

 than either of the normal ones, the lengths being normal prongs, 45^ and 27^ respectively ; additional prong, ls u . 



t Arcli.f. Xuturg., Jahrg. xxix, Bd. i (1863), Taf. v, fig. 3. 



J 46 Jahresber. Schles. Ges. (1868), 1869, p. 67. 



(ROY. soc. F.DIN. TRANS., VOL. i., ii:< i 



