CYBELE LOVENI. 127 



Bemads. — The carefully executed figure and minute description of Cybele 

 loveni given by Linnarsson, 1 and the large series of finely preserved specimens in 

 Mrs. Gray's collection from Thraive Glen, including some nearly perfect individuals 

 with numerous head-shields, thoraces, and pygidia, have led me to identify this 

 Girvan form with Linnarsson's species rather than with Portlock's G. rugosa, 5 to 

 which Nicholson and Etheridge referred the similar but poorer examples from 

 Drummuck. The examination of Portlock's type specimen of C. rugosa fully 

 confirms my view. Furthermore, M'Coy's 3 specimen of the latter species from 

 Coniston, though closely allied to the Girvan form, cannot be considered identical 

 with it. 



There are a few minor points in which the Girvan specimens differ from the 

 Swedish G. loveni, and they are sufficient to indicate a definite variety. The 

 characters of the head-shield agree exactly with those of G. loveni, Linnarsson, 

 except in (1) the presence of a small projecting knob in front of the glabella 

 (preserved only in some specimens) ; (2) the glabella does not increase in width 

 anteriorly, but is parallel-sided ; and (3) the fused lateral lobes of the glabella form 

 a rather narrower zone on each side. 



The thorax agrees, apparently in all respects, with that of C. loveni, the 

 prolongation of the sixth pair of pleuras into extraordinarily long free curved spines 

 to some distance behind the tip of the pygidium being beautifully exhibited in 

 many of the Girvan specimens. 



The pygidium, however, shows several points of difference ; it is narrower in 

 shape ; the axis is rather longer, being about three fourths the total length of the 

 pygidium, it is regularly conical and tapers more slowly, the sides converging 

 posteriorly at about 20°. There are 22 — 28 rings on the axis, interrupted along 

 the middle line for the whole length of the axis, and generally devoid of tubercles. 

 (In G. rugosa tubercles are situated at intervals along this space, but only one 

 of our specimens shows two minute tubercles, one at the fifth and the other at the 

 eleventh ring.) Behind the axis is a narrow-pointed post-axial piece. The lateral 

 lobes are elongate and narrow, being nowhere wider than the front end of the axis. 

 They each consist of three pleurae and one half-pleura. The first pleura is divided 

 by a median groove into two equally strong and tuberculated ridges, arising 

 opposite the first three or four axial rings, and arching at first slightly outwards, 

 but then bending backwards and a little inwards. The outer (anterior) ridge is 

 prolonged along the side of the pygidium to end in a short free point bent 

 outwards. The second pleura is smaller and lies almost parallel with the axis : it 

 consists of a narrow anterior ridge and a slightly larger tuberculated posterior one. 

 The third pleura is still smaller and lies parallel with the axis; only the posterior 



1 Liuuarsson, ' Vestevgotl. Camb Silur. Aflagr.' (1869), p. 63, pi. i, fig. 14. 



2 Portloclc, ' Geol. Eep. Londond.,' p. 302, pi. v, fig. 10 (Ogygia rugosa). 



3 M'Coy, ' Synops. Pal. Foss "Woodw Mus..' Appendix A, p. iii, pi. i g, fig. 8. 



