454 Miscellaneous. 



On the Megalactylu^ polyzelus of Ilifchcod: By K. 1). Cope. 

 This genus was named by Hiteheock in his ' Supplem3nt to the 

 Ichnology of New England,' p. 39, 18G-5 ; the bones have been briefly 

 describei in liis ' Ichnology,' on p. ISG. The remains were found, 

 in a more or less fragiuoulary cm lition, in the red-sandstoue ro<;ks 

 of the valley of the Connecticut, fro:n the neiglibonrhood of Spring- 

 field, Massachusetts. They were found by William Smitii, while 

 engaged in superintending some excavations made at the armoury, 

 which required blasting. 



The remains consist of four caudal and one dorsal vertebrae, the 

 greater part of the left fore foot, witli distal portions of the ulna aud 

 radius, the greater part of the left femur, proximal end of left tibia, 

 greater part of left tibula, tarsus, and hind foot, including a tarsal 

 bone, perfect metatarsus, proximal cud of a second metatarsus, parts 

 of the distal end of a thii-d, and parts aud impressions of four ])ha- 

 1 luges. 



These fragments demonstrate the former existence in the region 

 in question of a typical form of the suborder or order Symphypoda 

 (Compsorfiiatha, Huxley), and one nearer the birds than any other 

 hitlierto found in America. Its pertinence to this order is shown 

 by the absence of the first series of tarsal bones, apjjarently (a? 

 Gegenbaur has suggested, and as the structurL' of L^laj)s proves) in 

 consequence of their confluence with the distal extremities of the 

 tibia and tibula. This important character is apparently assumed 

 earlv in life in the present genus and in Compsor/nathus, and proba- 

 bly quite late in Ornithotarsus. In Compsojiuithas the additional 

 peculiarity of the persistence of but two carpal bone s is i)resenfed, 

 which, according to Gegenbaur, should corres])ond with those of the 

 first row of ordinary Keptilia, while those of the second have disap- 

 peared. In Mer/aditcti)ht^ those of the first S(!ries are present, viz. 

 the radial and probably ulnar, and one of the second row, very 

 much reduced, opposite to the second metacarpus ; there is space 

 for a second one of the second series, but it does not apjjcar in the 

 matrix, while the ulnar is probably lost. 



The bird-like tendencies of the Symphypoda have been indicated 

 above; and the very ornithic character of the bones of the present 

 form is also very marked. The walls of the long bones are very 

 thin ; in some places near their extremities almost as thin as 

 Avriting-paper. The vertebrae and ischia present the same thin walls ; 

 the structure of these walls is exceedingly dense. 



Prof. Cope next gives the special characters of the bones, which 

 are here omitted. He adds: — 



That animals of this genus made some of the tracks similar to 

 those of birds in the red sandstones of the valley of the Connecticut 

 there can be no doubt. It furthermore ex]ilains some ])roblematical 

 impressions which are occasionally found with them. Tracks of an 

 animal resting in a jdantigrade position, as indicated by the moulds 

 of two long parallel metatarsi, each terminated by three toes, are 

 accompanied by a ])eculiar, bilobate, transversely oval mark on the 

 middle line, some distance behind the heels. 



