LOVENECHINUS. 327 



This species includes specimens of various sizes and many localities, but as the structure 

 in all is essentially the same, as far as known, I consider them a single species. The specimens 

 from Llysfaen (Plate 35, fig. 6; Plate 36, figs. 7, 8) and from Kirkby Stephen (Plate 35, fig. 7; 

 text-figs. 240-243, p. 331) are much larger than the other known specimens. It is possible that 

 these two may prove to be a closely related but distinct species. As they show no structural 

 differences, however, I consider them the same as the smaller specimens. 



Test spheroidal, or in one case moderately elliptical. Ambulacra narrow, composed in 

 each area of four columns of plates, which are narrow demi- and wider occluded plates in 

 each half-area, pore-pairs in that portion of each plate nearest the next adjacent interambula- 

 crum. Ambulacral plates low, covered with minute tubercles. From six to eight (or in the 

 Kirkby Stephen specimen five and a half) demi-plates equal the height of an adradial. Ven- 

 trally ambulacral plates are primaries with pore-pairs uniserial (Plate 36, fig. 2; Plate 38, 

 fig. 2). 



The interambulacra in all known specimens have four columns of plates in an area at the 

 mid-zone, the adradials being pentagonal, the median hexagonal. These plates bear minute 

 tubercles and corresponding spines, the latter known only in the Kirkby Stephen specimen. 

 The oculars as far as known (Plate 36, fig. 6; text-fig. 243) are small and fully exsert, an excep- 

 tional Palaeozoic character (p. 89). Genitals are wide, high, with from two to four genital 

 pores each (Plate 36, figs. 4, 6, 7; text-fig. 243). This last figure apparently shows a 

 madreporite as observed by Dr. Bather. Periproctal plates are not known. 



Lower Carboniferous, 1'Ardoisiere, Central France, cotypes in the possession of the family 

 of the late Prof essor Julien ; Hunsriicken, Germany (Tornquist); Hook Head, County Wexf on 1, 

 Ireland, Science and Arts Museum Collection, Dublin; Helsington Barrows, southwest of 

 Kendal, Westmoreland, Museum of Practical Geology Collection 16,301; Armagh, Ireland, 

 two specimens, British Museum Collection E 10,051, and E 10,052; Llysfaen, near Llandulas, 

 Wales, British Museum Collection E 3,432; Kirkby Stephen, Westmoreland, England, York- 

 shire Philosophical Society Museum Collection; Marbre Noir de Dinant, Belgium (Fraipont). 



I will consider now the several recorded specimens, with the principal features of each. 

 Professor Julien's types from 1'Ardoisiere, as gathered from his figures and description, have 

 four columns of ambulacral plates in an area, wide occluded and narrow demi-plates, which 

 latter alone reach the interambulacra. Two pores are in each plate, situated near the marginal 

 suture. Ambulacral plates are low, six equaling the height of an adambulacral plate. Inter- 

 ambulacra with four columns of plates in an area, the plates being pentagonal in adradial col- 

 ums, and hexagonal in the median columns. According to Julien, the adradial plates measure 

 6 mm. in width by 5 mm. in height, the hexagonal 7 mm. in width by 5 mm. in height. They 

 do not show any imbrication. Ambulacral and interambulacral plates alike with numerous 

 small granulations, which Julien says do not merit to be called tubercles, but I do not see that 



