412 SCHULTE, SEI WHALE. 



maxillary fibro-cartilage. From its caudal margin a fasciculus of considerable relative size 

 diverges at an angle and becoming tendinous is inserted into the dense fibrous tissue which 

 invests the auditory bulla, on its ventro-lateral aspect extending as far as the base of the styloid 



process. 



The external pterygoid, is placed at the lateral margin and partly under cover of the fore- 

 going. It is a small cylindrical muscle arising from the junction of external and internal 

 pterygoid plates, and is directed caudad, laterad and slightly ventrad to its insertion upon the 

 front of the temporo-maxillary fibro-cartilage. 



Carte and MacAlister describe a single pterygoid, which "was inserted into the lower jaw 

 near its angle, sending some of its posterior fibers to be inserted into the interarticular fibro- 

 cartilage." This they regard as an external pterygoid. It is preferable, however, to regard 

 such single pterygoids as having failed to differentiate into internal and external portions. 

 Certainly the majority of the bundles in their description of B. acuto-rostrata have the in- 

 sertion of the internus. Beauregard in B. sibaldii (=B. musculus) mentions, but does not 

 describe, two pterygoids crossing the temporal tendon at an acute angle. In Phoccena (Rapp, 

 Stannius) both pterygoids are present, and the internus extends upon the auditory bulla. 



Facial Muscles. The forehead is covered by a broad thin sheet of muscle which arises 

 from the epicranial aponeurosis. The fasciculi have a longitudinal course and extend upon the 

 rostrum. Here the deep fasciculi turn ventrad and are inserted into a rough area upon the 

 maxilla which extends transversely across that bone and is bounded in front by a high sharp 

 ridge. Of the superficial fasciculi the mesal are inserted into the lateral margin of the nostril 

 in its whole length, a few reaching the midline of the rostrum just in front of it, while others 

 taking a somewhat deeper course are attached to the back and mesal wall of the narial passage. 

 The lateral superficial fasciculi spread out upon the transverse muscle of the rostrum, to some 

 extent blending with its bundles but in the main lying superficial to them. Caudad the epi- 

 cranial aponeurosis is attached to the margin of the supraoccipital. In this situation there 

 seemed also to be muscular fasciculi but I was not able to determine their presence with cer- 

 tainty. This muscle is apparently better developed than in Carte and MacAlister's Balcenop- 

 tera and far more so than in Megaptera, where it has no insertion upon the maxillary. In both 

 it is the most superficial muscle of the region, though Carte and MacAlister assign it to their 

 second or middle layer. Its function must be to draw the blow holes caudad, though from 

 its general position it is most conveniently designated occipitofrontalis. 



At the lateral margin of the frontalis and in part continuous with it is placed a second muscle 

 of longitudinal course. This lies upon the supraorbital margin arising from it and from the 

 adjacent temporal fascia. In front of the orbit its fasciculi turn ventrad, for the most part 

 to be inserted into the transverse rough area and ridge upon the maxillary lateral to the frontalis. 

 The more superficial bundles are continued upon the transverse muscle of the rostrum and 

 inserted into the fibrous tissue of the lip. Owing to the mesal concavity of the supraorbital 

 margin a portion of this muscle rests against the globe of the eye, ectal to its musculature and 

 aponeuroses. Its contraction would seem to entail a depression of the eye ventrad. In Megap- 

 tera it is far smaller, arises only from fascia and is separated from the eye by the prominent 

 margin of the orbit. Its function here would seem to be that of an elevator of the lip. Carte 

 and MacAlister describe a muscle of their second plane arising from the anterior edge of the 

 temporal fossa and from the maxilla and inserting upon the median raphe", the lateral lip of the 



