16 THORELL & LINDSTRÖM, SILURIAN SCORPION FROM GOTLAND. 



Length. Breadtli (greatest). 



5th dorsal plate of abdomen 3,5 7,3 



6tli segment » » _ 4 8,9 



6th dorsal plate » » _ 4 7,5 



7th segment » » -. 4,5 8 



Its breadth behind __ — 5 



Tail ..- - 26 (at least) 4,5 



Its 1st segment __ 4,1 4,5 



« 2nd » - 4 4,1 



» 3rd » .._ _ _ 4,5 3,7 



» 4tli » - 4,7 3,5 



» 5th » -- 4,25 3,5 



)) 6th » (without the sting) ___ 2,5 2,6 



Sting.. 2,2 (?) 1 



Mandible ? 2,7 



Its movable finger 3 1,1 



Palpus _ 24 5 



Scapula (trochanter joint) 3,5 3 



Humerus (femoral » ) 5,1 3,1 



Bracliium (tibial » ) 4,2 3 



Hand (with fingers) 11,2 (at least) 4,9 (at least) 



Its movable finger 8,1 1,5 



Legs, 1st pair 6,25 (?) 1,5 (?) 



» 2nd » 8,5 1,8 



» 3rd » 10,3 (?) 2,1 



» 4tli )> .' 10,7 (?) 2,2 (?) 



Trochanter of 2nd pair 1,4 1,8 



Fenmr » » » 1,5 1,8 



Tibia » » " l,s 1,5 



1st tarsal joint of 2nd pair 0,8 0,9 



2nd » » » » » 1,6 0,75 



3rd » » » » » 1,5 0,45 



Locality and geological Horizon. — Our specimen was found in the »Vattenfallet» 

 ravine south of Wisby, in a stratum of thin marly clay, of Ludlow age, probably be- 

 longing to the base of the Upper Ludlow series. 



