ON A NEW SPECIES OF TROPIDONOTUS FOUND IN WASHINGTON. 



Ky E. ». C 0I»B:. 



A small Miitersuake amis taken uear the central istation of the U. S. 

 Fish Commission known as the old Armory, in Washington, and was 

 sent to the National IMuseuni by Mr. J. B. Brown. Alter considerable 

 examination of the sijecimen I have concluded that it cannot be prop- 

 erly referred to any of the species of the genus to which it belongs, tlie 

 Trcpidonotus of authors. 1 therefore, with considerable surprise at the 

 necessity for so doing, name and describe it as follows: 

 Tropidonotus bisectus, sp. uov. (U. S. Nat. 2klus. No. 14643.) 



Scales in twenty-five longitudinal rows, all keeled. Form moderately 

 robust. Internasals nearly triangular; prefrontals wider than long; 

 frontal with i)arallel sides, which are longer than the anterior border. 

 Ivostral broad, low, divided in two by a vertical suture. Loreal higher 

 than long. Oculars 2-3, the superior anterior shorter than the inferior; 

 the inferior posterior so produced forward as to exclude the fifth supe- 

 rior labial from the orbit. Superior labials nine, the fourth only enter- 

 ing the orbit. Temporals l-o, the superior of the second series elon- 

 gate. Gastrosteges, 143 ; urosteges, 07. The color is olive- brown above, 

 dirty white below. There is a row of blackish spots along the sides, of 

 small size, which cover the adjacent parts of three scales of the first and 

 second rows, and which are separated by an interspace of one and a half 

 scales. These spots are wanting from the anterior fourth of the length. 

 Above the interval between them there is, on each side, a longitudinal 

 dusky spot, which is entirely separate from that of the opposite side. 

 These longitudinal spots commence at the head and disappear near the 

 middle of the length, after acquiring a tendency to extend obliquely 

 downwards and backwards. Head without marks, except three ])ale 

 spots on the parietals; one on ciich side of the median suture, and one 

 at the angle of the frontal. Belly unicolor, except at the lateral spots, 

 which extend over the posterior angle of the gastrosteges. Inferior sur- 

 face of tail black-speckled. Total length, 271"""; of tail, 00"'"'. 



The only ^Xortii American species with which this Ibrm can be com- 

 pared is the Tropidonotus icoodhousei B. & G,, of Texas. That species 

 only has twenty-five series of scales and nine superior labials, but it 

 has but one preocular plate and a totally difl'crent coloration, which is 

 like that of the T. Hipedon. The ])eculiar vertical division of the rostral 

 plate may be abnormal, but it is associated with a depressed form which 

 is not found in the T. u-oodhoutici. 



Of the true habitat of this species no conjecture can be made. Its 

 apparent immaturity renders it inobable that it is native to the region 

 in Avhich it was found, but it may have been-ln-ought to the Armory 

 concealed in freight. In anv case it is Korth Ameiqcan, and belongs to 

 the group of which T. Ja.sdalK.s is the type. 

 14G 



