JDr. H. Woodward — Tlte Position of the Merostomata. 297 



of explanations of plates, with a full index at the end). It is 

 delightful to find in these massive tomes such a grand collection of 

 materials relating to the American Merostomata, which the authors 

 have themselves brought together so carefully and studied and 

 described with so much patience and acumen, nor has the contemporary 

 foreign literature on the group been neglected, for every writer will 

 find his work and observations duly recorded and acknowledged. 



The volumes just issued by the New York State Museum make us 

 acquainted with no fewer than sixty-six American species, ranging 

 from Professor Walcott's Beltana Danai, Echmognathus Clevelandi, and 

 Stralops Thatcher i of Cambrian age to the Eurypteri of the Coal- 

 measures. No Limuli are recorded, but they are accepted as next of 

 kin to the Eurypterids on the one hand and to the Scorpions on the 

 other. 



Of actual complete forms of American Eurypterids known and figured 

 by Clarke and Ruedemann in their memoir (vol. ii), may be cited — 



Strabops Thatcheri, Beecher. Upper Cambric. 



Eurypterus remipes, De Kay. Siluric. 



E. lacustris, Harlan. Bertie Waterlime. 



E. ranilarva, Clarke. Lockport Limestone. 



E. Dekayi, Hall. Waterlime. 



E. inicrophthalmus, Hall. Manlius Limestone. 



E. Maria, Clarke. Shawangunk Grit. 



E. Kokonioensis, Miller & Gurley. Waterlime. 



Eusarciis scorpionis, Grote & Pitt. Waterlime. 



E. Newlini, Claypole. Waterlime. (Size, 26 X 13 inches.) 



Dolichopterus macrocheirus, Hall. Waterlime. 



Stylonurus longicaudatus, Clarke. Waterlime. 



S. excelsior, Hall. Catskill Beds. (56 inches long.) 



S. cestrotus, Clarke. Shawangunk Grit. 



S. my ops, Clarke. Shawangunk Grit. 



Hughmilleria socialis, Sarle. Pittsford Shale. 



H. Shaivangunk, Clarke. Shawangunk Grit. 



Pterygotus Buffaloensis, Pohlman. Bertie Waterlime. 



P. macrophthalmus, Hall. Bertie Waterlime. 



To these must be added nearly fifty species described and figured 

 from more or less perfect remains, many of which, however, add 

 greatly to our knowledge of structural details of the group. 



The plates are admirably executed and show the minutest features 

 of each species. The eighty-eighth and last plate gives an enlarged 

 figure ( X 7) of Proscorpius OsbornifWhit^eld, Tipper Silurian, affording 

 a convenient comparison with Eurypterus and other Merostomes. 



The following fifty species are arranged in order from the Cambrian 

 to the Coal-measures: — 



Beltana Danai, Walcott. Greyson Shales, Montana. 



Echinognathus Clevelandi, Walcott. Utica Slate, Oneid Cap. 



Eurypterus megalops, Clarke. Frankfort Shale. 



E. pristinus, Clarke. 



E. stellatus, Clarke. 



Eusarcus triangularis, Clarke. 



E. (?) longiceps, Clarke. 



Dolichopterus f rankf or tiensis, Clarke. 



D. latifrons, Clarke. 



Hughmilleria magna, Clarke. 



