1868.] WOODWAIID — SILURIAN CRUSTACEA. 291 



As regards the form of the body-seginonts, Mr. Salter's evidence 

 is most vahiable in confirmation of the identity of these remains ; for 

 in the Survey Monograjih he figures (p. 101) five of the anterior 

 body-rings from Leintwardine, which agree closely in form with the 

 specimen from Lanarkshire. He also observes (p. 99) that " the 

 hinder segments were decidedly longer in proportion to their width 

 than in Pterygotus Anglkus, or Pt. yir/as" Indeed one of the seg- 

 ments which he has figured (Mon. pi. x. fig. 5) most clearly shows 

 this to be the case. 



From the evidence derived from the Lanarkshire specimens (de- 

 scribed hereafter), I venture to refer this form to Eury})terus ; it 

 will probably come near Hall's Eurypterus pachycheirus'^'. 



But the specimens from the Lower Ludlow rock give evidence of 

 a species twice the size of that occurring in Lanarkshire ; there are 

 also sufficient points of distinction in the form of the metastoma, the 

 joints of the swimming-feet, the armature of the palpi, &c. to spe- 

 cificall}^ distinguish them. I therefore propose to retain the name 

 of punctatus for the Ludlow remains, as indicated, adding thereto 

 (with a query) the great lip-plate here noticed for the first time 

 (PL IX. fig. 2). 



For the Lanarkshire specimens (PI. IX. fig. 1, and PI. X. fig. 2) 

 I propose to adopt Mr. Salter's MS. name scorjpioides, attached to the 

 specimen in the Jermyn- Street Museum. 



It is needless to enter here into a detailed description of the 

 remains of this well-marked species — Mr. Salter having already 

 done so, fully and ably, in the Monograph published by the Greolo- 

 gical Survey, already referred to. I will merely mention such parts 

 as are included in his description of this species, but which I see 

 reason to exclude therefrom. 



First, then, I would exclude the remains of the chelate antennae 

 — my reason for so doing being that all the species of Merostomata 

 with spinous palpi have small, simple antennules (e. g. Eurypterus, 

 Sfylo7iunis, Slimonia). 



Secondly, the lip-plate (Mem. Geol. Surv. Mon. I. pi. xi. fig. 4). 



The form of the lip-plate is very characteristic of the separate 

 divisions of this group ; and I am not aware of any other species 

 which possesses such ja metastoma as is found in E. scorpioides, and 

 which, from the detached plate now exhibited, I doubt not, also 

 marked E. punctatus, the Leintwardine species. I would there- 

 fore suggest that the detached lip-plate (Geol. Surv. Mon. pi. xi. 

 fig. 4) must have belonged to some other species — the form of the 

 plate being more near that of Slimonia acuminata. 



Thirdly, of the telson Mr. Salter observes that " it is yet wanting," 

 and that " in all probability it was not unlike that figured on pi. x. 

 fig. 11, which has possibly something to do with it." 



On the fragment referred to, I wdll not venture to give an opinion, 

 but will only observe that, as far as I can ascertain by a careful 

 comparison, such a form would certainly have had an ensiform 

 telson, as in the other Eurypteri, with which I venture to place it. 

 * And probably also near his subgenus Bolichopterus. 



