THE WHALEBONE WHALES OF THE WESTERN NORTH ATLANTIC. 81 
of the A. gbbosus, 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 oray whale or Agaphelus glaucus Cope, 22 inches 
in length, width at base 6 inches. "Tn the former near ly 6 in an inch, in the latter 24. 
The baleen of the A. gibbosus belonged to an immature specimen of 35 feet in 
length.” (28, 159-160.) ! 
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, 198). 
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 (Orca),” 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 BALASNOPTERA Lacépéde. 
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 a entrance of Chesapeake Bay, 
between York River and een anenneee River, Aug. 11, 1858. 
Type-specimen: Skeleton of “an ndule 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 
osphyia, which he had described a short time before. Later in the same year he 
concluded that it represented the Stbbaldius laticeps of Gray (24,297). It was not 
until 1869 that he finally decided that the whale represented a new species, which 
"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.” 
