THE WHALEBONE WHALES OF THE WESTERN NORTH ATLANTIC. 81 



of the A. gibbosus, was longer and had narrower basis. The plates moderately and 

 simply concave, while those of the latter are sigmoidal, most curved near the outer 

 margin in cross section. The bristles of the California species were very coarse, 

 varying from one to three series between the enamel plates. The bristles of 

 the A. gibbosus much finer, three series together. Length of the latter 8.5 inches, 

 width at base 4.4 inches. In the gray whale or Agaphelus glancus Cope, 22 inches 

 in length, width at base 6 inches. In the former nearly 6 in an inch, in the latter 2^. 

 The baleen of the A. gibbosus belonged to an immature specimen of 35 feet in 

 length." (28, 159-160.) J 



In the same year, Cope mentioned the species again under the name of 

 Agaphelus glaucus in a list of the Cetacea of the coasts of North America 

 (27, 193). 



A little later in the year 1868 he published a full description of two specimens 

 observed at Monterey, Cal., Jan., 1866, by Mr. William H. Dall, and a set of whale- 

 bone in the Essex Institute. This was in an article entitled, " On Agaphelus, 

 a genus of toothless Cetacea " (26, 226-227). The whalebone was that described 

 earlier in the year, and must be considered as constituting the type-specimen. The 

 Monterey specimens consisted of a nearly complete skeleton, and a specimen in the 

 flesh, " killed by Killers (Oreo)" sufficiently complete to allow of external measure- 

 ments and notes on the external characters and coloration. Two skulls were 

 obtained by Mr. Dall at Monterey, at a later date, one of which was deposited in 

 the museum of the California Academy of Sciences, and the other in the National 

 Museum (Cat. No. 13803, U. S. N. M.). 



In 1869, Cope erected the genus Rhachianectes for this species (83, 15). 



Genus BAL^ENOPTERA Lacepede. 

 3. SIBBALDIUS TUBEROSUS Cope. 1869. 



Original description: Proceedings, Academy of Natural Sciences, Phila., 1869, 

 p. 17. Presented for publication, March 9, 1869 ; published, July 20, 1869. 



Type-locality : Mobjack Bay, Virginia, near the entrance of Chesapeake Bay, 

 between York River and Rappahannock River, Aug. 11, 1858. 



Type-specimen: Skeleton of "an adult male." Captured by Dr. P. A. 

 Taliaferro and Prof. Edwin Taliaferro of William and Mary College, Williamsburg, 

 Virginia, " and prepared and set up " (where ?). 



A passing allusion to the specimen on which the species was founded was 

 made by Cope in 1865 (22, 168). In 1866 he published a brief description of the 

 specimen, drawn up by Prof. E. Taliaferro (23, 8), but referred it to his Megaptera 

 ospJiyia, which he had described a short time before. Later in the same year he 

 concluded that it represented the Sibbaldius laticeps of Gray (24, 297). It was not 

 until 1869 that he finally decided that the whale represented a new species, which 



1 These numbers and all similar ones following refer to the bibliography at the end of the 

 volume. The letters "sep." indicate that the paging is from a reprint or "separate." 



