No. l8.J TRIASSIC FISHES OF COXNECTICUT. 63 



notched behind, the posterior extremity prolonged instead into a 

 fine point. Fins strong but relatively short-based, the caudal 

 rather prominently furcate and with about seventeen rays. Dor- 

 sal, anal, and pectoral fins with about fourteen fulcra each, the 

 ventral with about twelve. Apparently four dorsal fin-fulcra 

 originate on the dorsal line over the basal supports, the fifth 

 being slightly less than one-half the length of the anterior fin- 

 margin. The fin-formula is stated to be as follows: 



D. 9-10; C. 17; A. 9; P. 12. 



This is one of the largest and most striking of the fossil fishes 

 OQCurring within the Connecticut Valley region, easily recognized 

 by its gracefully proportioned outline, regular and heavy squama- 

 tion, and thickness of head bones. Less abundant than either 

 ^. tenuiceps or ^. fultus which accompany it, it is distinguished 

 from the former of these by the following differential characters, 

 as was first pointed out by Newberry : the dorsal ridge-scales, 

 which are usually depressed, are less strongly developed than in 

 5". tenuiceps, and " the arch of the back does not show the 

 hump which is so characteristic of that species ; the fins are very 

 strong; the fulcra of the dorsal and anal fins unusually broad 

 and long, forming arches nearly half an inch wide at the base, 

 curving gracefully backward to a point." 



Remains of this species are common to both New Jersey 

 and New England, the locality near Sunderland, Massachusetts, 

 having furnished a number of excellently preserved specimens, 

 including the type of the so-called Ischypterus marshi. A photo- 

 graph of this particular individual is reproduced in Plate I of 

 the present Report, and in Plate II is shown the head portion of 

 the instructive example which served as the basis of Dr. Eaton's 

 restoration, published in 1905. The originals of both plates are 

 preserved in the Peabody Museum of Yale University, and 

 equally perfect and important material is to be found in the 

 American Museum of Natural History at New York. Other 

 interesting specimens are the property of Amherst College and 

 Wesleyan University, respectively. As long ago as 1845, the 

 distribution of this species was stated by J. H. Redfield to be as 

 follows : " Occurs at Sunderland, Mass. ; Westfield and Middle- 

 field, Conn.; Pompton and Boonton, N. J."^ 



> Quoted by Newberry in his Monograph on Triassic Fishes, 1888, p. 30. 



