PHACOPS. 



59 



Phac. (Cryph^eus) punctatus, Steininger ? PL I, figs. 17 — 19. 



Olenus punctatus, Steininger. Mem. de Soc. Geol. Fr., i, p. 356, vol. i. pi. 22, 1833. 



— — Emmerich. Dissertation, p. 55, 1839. 



Asaphus arachnoides, Goldfuss. Leonhard und Bronn's Neues Jahrbuch, p. 561, tab. 



v, fig. 3, 1843. 

 Calymene — Honinghaus, pamphlet, Crefeld, 1835. 



Pleuracanthus arachnoides, Milne-Edwards, Crust., iii, p. 329, 1840. 



— punctatus, Roemer. Rheinisch Uebergangs ., p. 82, 1844. 



Phacops arachnoides, Burmeister, Org. Trilob., 1st ed., 1843; 2d ed., p. 96, 



1846. 

 — laciniatus, Salter, in Morris's Catalogue, 2nd ed., p. 113, 1854 (not of 

 Roemer). 



Phacops (Crgphaus) " scuto capitis in medio marginis antici acuta, angulis posticis valde 

 productis ; limbo scuti caudalis decies spinosa." — Burm., 1. c. 



The only notices I can find of this as a British species are by myself — first, in the 

 Decades of the Survey, No. 2, under the description of P. caudatus, p. 8, where it is 

 referred to P. arachnoides of Goldfuss; and afterwards in Morris's Catalogue, 2nded., 

 1854, where it is referred, I think wrongly, to P.. laciniatus, Roem. The fragments 

 known were so very obscure, that enough could only be seen to make it certain we had 

 one of the species of this remarkable group, in which the tail- margin has undergone its 

 fullest expansion. 



In order to give the English collector a notion of what 

 he may expect to find, I have drawn a perfect specimen from 

 Germany, nearly following Burmeister. And, after comparing 

 with the best specimens at my command, I think the first refer- 

 ence was right, and that the British species is the well-known, 

 but still rarely perfect, Olenus punctatus of Steininger, a name 

 which should have been retained for this fossil, as Stein- 

 inger's figure is quite recognizable. 



I purposely avoid describing the British fragments, as the 

 inspection of the plate will show that they only indicate a 

 species with narrow, long glabella, with tolerably equal lobes, 

 a granulated surface, a pointed front to the head (not pro- 

 duced, however, as in the foreign specimens), and longer head- 

 spines than in the German specimens. The eyes appear to be 

 not quite so large. 



The tail shows ten spines, which are rather shorter, less convergent, and more radiating 

 than Eifel specimens warrant. 1 But they are narrow, not broad, fin-like plates, as in 

 P. laciniatus, and longer, too, in proportion than in that species ; the glabella, too, is nar- 



1 Goldfuss's figure is more faithful than Prof. Burmeister's. 



Fig. 16. 



Phacops(CrypheBus)punctatiis,Stein., 

 from Burmeister's work. 



