THE 



GEOLOGICAL MAGAZINE. 



NEW SERIES. DECADE IV. VOL. VII. 



No. XI.— NOVEMBER, 1900. 



OISI<3-IIsr-A.Ij JLISTIGXiES. 



I. — Restoration of Stylo.vurus Lacoanus, a Giant Arthropod 



FROM THE Upper Devonian of the United States.' 

 By Professor Charles E. Beechek, Ph.D., of Yale University, New Haven, U.S.A. 



(PLATE XVIII.) 



IN the animal kingdom the attribute of bigness has come to be 

 regarded as one of the prerogatives of the vertebrates. On this 

 account, invertebrates seldom receive credit for having a size of 

 more than a fraction of a cubit, and are looked upon as objects to be 

 lield in the hand or viewed under a lens. As a matter of common 

 experience, and probably also of congratulation, large invertebrates 

 are rare, and some whole classes cannot furnish a single individual 

 measuring more than a few inches in greatest diameter. 



In a list of arthropod giants the subject of the present note must 

 be included, and will take equal rank with the Giant Spider-Crab 

 of Japan (Macrocheira Kaempferi) and the great ' Seraphim ' of the 

 Scotch quarrymen (Ptenjgotus anglicus). The former can safely 

 claim to be the largest representative of the Brachyurans that has 

 ever existed, and to the latter may be accorded the same distinction 

 among the Mei'ostomes. 



The living species of the Merostomata comprise only the American 

 and Moluccan Horse-shoe Crabs, Limulus polyphenms and L. molnc- 

 canus. The latter sometimes attains a length of three feet and 

 measures eighteen inches across the carapace. To find other species 

 in this order worthy of comparison with the huge Brachyuran of 

 Japan it is necessary to go back to the Palfeozoic forms, and among 

 these the larger species of Pterygotus and the Stylonuriis here noticed 

 fill all the requirements. It should be borne in mind, however, that 

 these statements are based upon comparative lengths and breadths. 

 If bulk alone were considered, the common lobster (Homarus 

 americanus and H. vulgaris) should be mentioned, though in length 

 and extent of limbs it would be considerably smaller. 



Concerning the size of the Scotch ' Seraphim,' Dr. H. Woodward - 

 states that " From our present knowledge of the almost perfect 



' Reprinted from the American Journal of Science, vol. x, August, 1900, 

 pp. 145-150. 



- H. Woodward, " A Monograph of the British Fossil Crustacean belonging to 

 the Order Merostomata," pt. i, 1866 ; pt. iv, 1872, pp. 1-264, pis. i-xxxvi : 

 PaliToontographical Society, vol. xix. 



DECADE IV. vol.. VII. — NO. XI. 31 



