KtJNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 40. N:u 5. 37 



of bhe symphysis and extend from there in longitudinal rows along the mandible. 

 These tubercles are still better developed in the foetus alludecl to above and are 

 there arranged in three rows, (comp. Pl. IX). The upper one of these, near the 

 upper börder and anterior end of the mandible, consists of 4 tubercles, then comes 

 below and behind these a row of 3, and finally still lower, but extending from the 

 symphysial cluster and to below the posterior end of the second row a series of 

 6 or 7 tubercles (comp. Pl. IX). On Sörling's photos this arrangement is not quite 

 so plainly visible, partly in consequence of the barnacles. Three rows on the mand- 

 ible were also recognized by True (20) on the Humpback from Newfoundland. 

 The tubercles of the mandible of the foetus of the southern Humpback carried as 

 well as those of the maxillary each a hair which in some instances, however, had 

 not yet broken through the epidermis, although its tip made an elevation on the 

 same, in other instances it was well developed. 



The epidemi of these tubercles was smooth and similar to that of the sur- 

 rounding parts of the skin and did not show such a rugged surface as some forma- 

 tions found in the Black whale, and which will be spöken of låter on. It cannot 

 be said anything with certainty about these tubercles as there has not been any 

 material preserved for investigation. It appears, however, most likely that they 

 have a sensory function as the development shows that hairs corresponding to vi- 

 brissa? originally are placed on, and in these tubercles, and they are too largely 

 developed to be only rudiments of footstalls of former sensitive hairs or vibrissae. 



The baleen of the southern Humpback was quite black, Sorling says, except 

 that »one single specimen showed some yellowish outer margins.» The samples 

 Sörling has carried home are black, the coarser bristles at the tip are also black 

 but the finer on the inner side become, more or less, light brownish in a median 

 direction. 



Scandinavian authors, like Lilljeborg and Särs, describe the baleen of the 

 northern Humpback as »grey black» and the bristles as brown. Struthers found 

 anteriorly some of the baleen partly white. In a similar way True (20) observed 

 in one specimen from Newfoundland »the right whalebone - - — — from the an- 

 terior end backward about one foot — — — dull whitish», and in another specimen, 

 he says, »a few anterior blades of whalebone were white externally.» 



With regard to the size of the baleen it may be recorded that the largest piece 

 Sörling has carried home measures about 73 cm. in length or 2874 english inches. 

 True (20) has compiled a table of measurements indicating not only the length of 

 the baleen of Newfoundland Humpbacks according to his own observations, viz. 

 21 — 22 inches, but also the records in the literature about the same of European 

 specimens viz. 20 to, approximatively, 24 inches. It would appear from this, as if 

 the southern atlantic Humpback had comparatively longer baleen, especially if it 

 is considered that the size of the whale itself is somewhat smaller. 



The length of the bristles is, of course, variable, but the long ones on the 

 middle of the median side seem to have an average length of 18 — 20 cm. (7 — 8 in.) 

 and many are from 23 to 28 cm. (9—11 in.). The length of the bristles have not 



