724 PROF. W. H. FLOWKR ON THE [DeC. 19, 



son, and others, until Dr. Gray, in the 'Zoology of the 'Erebus' and 

 'Terror" (184(5), described and figured a cranium, received into the 

 British Museum from the Orkneys, as that of a distinct species, 

 which he named Hyperoodon latifrons (p. 2? and plate 4). The 

 diagnostic character is: — " Skull large, heavy, solid, the reflexed part 

 of the maxillary bones very thick and thickened internally, so as 

 nearly to touch each other in front of the blower, much higher than 

 the hinder part of the skull ;" whereas of H. rostratus it is stated 

 that " the elevated plates of the maxillary bones are thin, leaving a 

 broad space between them in front of the blowers, and as high as 

 the frontal crest." 



Professor Eschricht, who had devoted great attention to the 

 anatomy, development, and life-history of the Cetacea, expressed, 

 in his valuable memoir on Platanista, the opinion that Dr. Gray's 

 H. latifrons was nothing more than an old male of the ordinary 

 form \ This opinion called forth a long rejoinder from Gray", in 

 which he endeavours to show that males and females of both forms 

 have been met with, and moreover states that " he was assured by 

 the fishermen who procured the head which he described and 

 figured that it was that of a female gravid with young." 



So convinced was Gray of the distinction, that in 1863 (see P. Z.S. 

 18t)3, p. 200) he constituted H. latifrons into a distinct genus 

 called Lagenocetus, and retained it in this position in all his sub- 

 sequent cetological writings. 



Since the type specimen was described by Gray, not only several 

 skulls but also complete skeletons have been met with of the larger 

 form, a very fine specimen being mounted in the Copenhagen Museum 

 and- another at Caen. Although there is certainly nothing except size 

 and the form of the maxillary crests to distinguish them from the 

 more common form, there is so striking a difference in the shape of 

 the skull, that Dr. Gray's opinion, backed by the various statements 

 made by him regarding the age and sex of the different individuals 

 recorded (all of which perhaps will not bear close investigation), has 

 induced many zoologists to agreed with liini, at all events as to 

 the specific distinction, and to admit H. latifrons into the list of 

 Cetaceous animals, sometimes as a doubtful and sometimes as a well- 

 determined species. I had, in fact, myself done so in the article 

 " Mammalia" written in the beginning of this year for the ' Encyclo- 

 paedia Britannica,' being fortified in this opinion by some premature 

 information derived from the same source as that which has now 

 dispelled this view (as mentioned in a note to p. 395 of the present 

 volume of our Proceedings), and especially because my friend the late 

 Prof. Reinhardt, whose recent death is a great loss to this branch of 

 zoology, had fully adopted Gray's view ^. 



' See the English translation in Ann. & Mag. Nat. Hist. ser. 2, ix. p. 281 

 (18.52). 



- Ibid. p. 407. 



^ He says: — "Eschricht meente, soni bekjendt, at Hyperoodon latifrons kun 

 var opstillet paa den ret gamle Han af den almindelige D^gling, Hyperoodon 

 rosfratus; men Gray's Art niaa nu ausees tor vel begrundet." — Vidensk. Selks. 

 Skr. 5 E«kke, naturvidens. og math. Atd. 9, B. 1 (1869). 



