536 MISS CROSFIELD AND MISS SKEAT ON THE [Aug. 1 896, 



distance out, and then gently decurved. Obliquely grooved through- 

 out their length ; ends rounded anteriorly, but with exceedingly 

 short sharp points curving backward, closely resembling those of 

 Cyclognathus micropygus. 



Pygidium very small, much broader than long. Axis wide, 

 marked with three rings, not continuous across. Terminal portion 

 small. Side lobes with two or three faint furrows. Margin 

 entire? A single rolled-up specimen was found at Nant-y- 

 Glasdwr. 



We recognize this species as belonging to the genus Peltura, 

 Milne-Edw., from the forward position of the eyes, their small 

 size, the rounded genal angles, and the pointed pleura; but we 

 refrain from placing it in any of the recognized subgenera. We 

 consider it closely related to the species of the subgenus Peltura 

 (sensu stricto), Ang., and yet more so to those of Cyclognathus, 

 Linrs. This latter subgenus is, however, too ill denned to be of 

 practical use as it stands. The chief distinctions between Cyclo- 

 gnathus, Linrs., and Peltura (sensu stricto), Ang., are that in 

 Cyclognathus the glabella-f arrows are indistinct or absent, and the 

 pygidium is generally small, with an entire margin ; in Peltura, on 

 the other hand, the glabella-furrows are distinct and the margin 

 toothed. Cyclognathus transiens, Brog., however, bridges over the 

 gap between the two subgenera by having teeth on the margin of 

 the tail ; further, in Cyclognathus costatus, var. minor, Brog., the 

 glabella-furrows are as distinct as in Peltura scaraboeoides. 



Brogger also shows that Linnarsson's distinction, based on the 

 small size of the tail in Cyclognathus, does not hold. For this 

 reason we refer this new form simply to the genus Peltura, Milne- 

 Edw. 



It differs from Peltura scaraboeoides, Wahlenb., in the shape of 

 the glabella, which is parallel-sided, not parabolic, and in the shape 

 of the fixed cheeks. These in P. scaraboeoides taper more towards 

 the anterior end, and do not extend so far forward. The new form 

 has a row of puncta in the groove between the anterior border and 

 the glabella, the pleura do not taper towards the ends, and the 

 points of these are much shorter than in P. scarabceoides. The 

 pygidium is also here very much smaller, and the margin appears to 

 be entire, not toothed. The free cheek is very much narrower than 

 in any species of Peltura. The form of the pleura and fixed 

 cheeks, the punctate border and entire margin of the tail al^o 

 distinguish this form from Peltura biclentata, Brog., and the latter 

 feature from P. planicauda, Brog. In the shape of the pleura it 

 approaches very nearly to Cyclognathus micropygus, Linrs. : the 

 pygidium seems to be intermediate between those of Cyclognathus 

 micropygus, Linrs., and C. costatus, Brog. ; but the head differs 

 widely from either of these. 



Localities and Horizon : Nant-y-Glasdwr, Cwm Pfrwd, Cwrt 

 Hir, Carmarthen. Tremadoc Slates. 



