﻿BIBLIOGRAPHY OP THE MEROSTOMATA. 25 



living family, and was in aspect more like the larvse than the adult forms of any Crus- 

 tacean with which we are acquainted." 



35. Later in the same year Sir R. I. Murchison 40 gave an account of the discovery, 

 by Mr. Robert Slimon, of a remarkable series of Pterygotian remains at Lesmahago, 

 Lanarkshire, in which he observes that the uppermost Silurian Strata in Russia, in 

 England, and in North America, are characterised by the presence of Pteryyotus and 

 Eurypterus, associated with small Linyulce and other fossils. 



36. 1856. Mr. J. W. Salter 41 follows with a description and figures of anew genus 

 of Pteryyoti, viz. Himantopterus, of which he there gives notice of six species, namely, H 

 maximus and acuminatus (now united in Slimonia acuminata), H. bilobus, H, perornatus, 

 H. Banksii (now referred to Pteryyotus) and H. lanceolatus (since referred to Eurypterus). 



37. 1856. Prof. T. H. Huxley 43 adds some observations on the structure and 

 affinities of Himantopterus. The conclusion he draws is that " The nearest approach to 

 Himantopterus which could be constructed out of the elements afforded by existing 

 Crustacea would be produced by superinducing, upon the general form of a Cumoid 

 Crustacean, such a modification of the appendages as we find among the Zoseform 

 Macruran larvse." In fact, that Himantopterus bears a strong similarity to a larval form, 

 but is not itself therefore to be considered embryonic. 



38. In 1856 Dr. H. Jordan and Hermann von Meyer 43 described a curious 

 (blind) Crustacean from the Culm-formation of Saarbruck under the name of Adel- 

 ophthalmus {Eurypterus) yranosus, Jord. ; also the fragment of a second remarkable form 

 which is named Arthropleura armata, Jord. 



39. 1856. Mr. David Page 45 gives figures of Pteryyotus, Himantopterus, Stylonurus, 

 and Slimonia, and observes, " Respecting these Crustaceans, their place is altogether 

 unknown in zoology, there being, as it were, an interfusion of phyllopod, pcecilopod, and 

 decapod, — of brachyurous, macrourous, and xiphosurous forms." 



40. In Prof. T. H. Huxley's 46 ' Lectures on Natural History,' published November 

 7th, 1857, appears the following description of the Eurypterida .- — " This group includes 

 the Devonian and Silurian genera Eurypterus and Pteryyotus, which, though as little 

 embryonic in their characters as the Trilobita, are, in many respects, curiously larval. 

 These singular Crustaceans attained a very great size, species of Pteryyotus of several 

 feet in length being known. The body, in those forms which have been most carefully 

 examined, consists of a comparatively small carapace, rounded anteriorly, and carrying on 

 its upper surface a pair of elevations, which are distant in Pteryyotus and approximate in 

 Eurypterus, and were, in all probability, the eyes. 



" Ten to twelve distinct segments succeed the carapace, becoming narrower posteriorly 

 to the last, varying in shape from lanceolate to oval, and deeply emarginate, probably repre- 

 sented a telson. 



" Three pairs of appendages were attached to the carapace in Pteryyotus — anterior 

 pincer-like antennae ; median toothed mandibles, provided with a large palp ; and a pair 



