ON EURYPTERID-BEARING DEPOSITS OF THE PENTLAND HILLS. 303 



belonging to four genera. One of these, a specimen — unfortunately badly 

 preserved — of Pterygotus, is new to this locality, and is in all probability 

 new to science. It is allied by the form of the telson to Pt. anglicns 

 from the Old Red Sandstone rather than to the common Silurian form 

 Pt. bilobus. It is the first species with a pointed telson from the Silurian, 

 of this country, though this form of telson has been described by Pohlmann 

 from the Buffalo Limestones of America. 



The genus Eurypterus is also only represented by a single specimen, 

 which, though much larger than the type specimen, I am inclined to refer 

 to Eurypterus conicus. 



Sfylonurus ornatus, the large form from these beds, is represented by a 

 considerable number of specimens, mostly fragmentary. One specimen 

 shows the body minus the carapace and telson to have been 10 inches in 

 length. The details of a number of the appendages have been made out, 

 including the two posterior pairs which are the long walking legs charac- 

 teristic of the genus. The posterior of these has a length of 9 inches, the 

 anterior of about 7^ inches. In front of these two appendages I have 

 made out representatives of two other pairs of limbs, both of which are 

 furnished with long spines. The detailed description of these and other 

 points of interest must, however, be postponed till a more thorough investi - 

 gation has been made. 



The other species of Stylonurus which occurs in these beds — St. mac- 

 roj)hthalmus — is well represented. One specimen is almost complete, only 

 wanting the telson and part of one side of the body. It shows four 

 appendages down one side. The two posterior limbs are more unequal in 

 size than is usual in this genus, the anterior one being far more slender 

 than the posterior and only two-thirds its length. The appendages in front of 

 these do not appear to be so well furnished with spines as in St. oniatnif. 

 Another specimen of this form, though very fragmentary, has shown, after 

 careful development, five legs down one side of the carapace. They have 

 not yet, however, been fully worked out. There are various other fragments, 

 showing parts of the body, tail spines, itc. 



Of the other form occurring in these beds, Drepano'pteTus jientlandicus, 

 we have been fortunate enough to secure one almost perfect specimen, 

 which shows the form of the body and three pairs of limbs. The form of 

 the last pair of limbs but one confirms the relationship of this form to 

 Stylonurus. There are many other more or less fragmentary specimens, 

 which may be expected to yield further information as to the details of 

 this interesting genus. 



Besides the Eurypteridse the bed has yielded a considerable number of 

 other fossils, among which may be mentioned : Graptolites, various Poly- 

 zoa, a species of Gomphoceras, Lingula and other brachiopods. These, 

 when properly identified, may be expected to yield important information 

 as to the exact horizon of the beds. 



In view of the large amount of material which yet remains to be 

 examined and the interest of the results which are briefly referred to above, 

 your Committee ask to be continued for another year with a further 

 grant. 



