380 



SCIENCE. 



[Vol. I., No. 14. 



copies, have been used to swell this chorus 

 of admiration. 



He has another craze. He chooses to as- 

 sert that there is a conspiracy among what 

 he calls ' the Morgan men ' to depreciate and 

 crush him, and that these two articles are part 

 of the plan. We suspect archeology is too 

 engrossing a studj- for such trivial bj'-play ; 

 and we know, also, that the editors, whom he 

 berates for lending themselves to such a plot, 

 found students in the field too inclined to 

 ignore his work, to bring themselves easily to 

 the be'stowal of any time upon criticising it. 

 It is piteous to think how what might have 

 been a useful labor is resulting in discredit and 

 personal intrusiveness. 



A STUDY OF THE HUMAN TEMPORAL 

 BONE. — I. 



It may be asked why the writer of the pres- 

 ent article should publish a subject which has 

 already been so thoroughly and repeatedly in- 

 vestigated, is so familiar, and is treated with 

 the utmost detail in manj' manuals of anatomy-. 

 In his experience as a teacher of anatomj', he 

 has, of necessity, been obliged to observe many 

 important points over and over again ; and, as 

 one of the results, he has been led to see some 

 of them differentlj' from the views commonlj^ 

 entertained. As no other bone is so complex 

 as the temporal, and none more important in 

 its relations, it occurred to him that his view 

 of it might prove of interest to students. No 

 discoveries are claimed, and it is probable that 

 what is here written may be found in previous 

 anatomical literature. In some points the de- 

 tails are less complete than those given in the 

 admirable, accurate, and exhaustive ' Hand- 

 buch der anatomic ' of Professor Henle ; but 

 others are perhaps more definitely indicated. 

 For brevitj', some of the more obvious details, 

 given in ever^- manual, are excluded. 



For convenience of studv. and reference, it 

 is usual to consider the temporal bone as con- 

 sisting of the squamous, mastoid, and petrous 

 portions, though these do not accord with the 

 natural divisions observed in its development. 

 To avoid circumlocution, the terms ' squamosa,' 

 'mastoidea,' and 'petrosa,' are substituted for 

 the ordiuar3' phrases 'squamous portion,' etc. 



The squamosa is the irregularly circular or 

 oval plate, upright in position, at the fore-part 

 of the bone. Its outer surface, nearly flat or 



feebly convex, forms part of the temporal fossa. 

 The inner surface is concave and pitted, as 

 usual in the other bones of the cranium, and 

 is marked by grooves for the great meningeal 

 vessels. It is eommonlj' defined hy a fissure of 

 variable extent, remaining as part of the petro- 

 squamosal suture. 



Projecting from the lower part of the squa- 

 mosa, externall}-, is the zygomatic process, 

 which articulates with the malar bone to form 

 the zygoma. The base of the process is broad 

 and strong, and has its upper surface slanting 

 forward. The upper sharp border of the pro- 

 cess is continuous backward with a curved 

 line, the temporal ridge, which defines the 

 squamosa from the mastoidea. 



The squamosa underneatli foi'ms the articu- 

 lar surface for the mandible, consisting of the 

 glenoid fossa with the articular eminence in 

 front ; both extending outwardlj' below the 

 root of the zygomatic process. The glenoid 

 fossa is a deep, transversely oval concavit}', 

 defined behind 'by the glenoid fissure. The 

 articular eminence is a transverse ridge of 

 variable thickness, convex fore and aft, and 

 more or less concave to straight transverselj'. 

 Variable prominences at the outer part of the 

 articular surface are the anterior and posterior 

 glenoid processes. 



The mastoidea is the outer back part of the 

 bone, externally defined from the squamosa hy 

 the temporal ridge. It is prolonged below into 

 the conspicuous nipple-shaped eminence, the 

 mastoid process. Internally, to the base , of 

 the process, is a large fore-and-aft groove, the 

 digastric fossa ; and internall}' to this again is 

 a narrow groove for the occipital artery. 



The broad archwaj' between the mastoid and 

 post-glenoid processes is formed by the audi- 

 tory plate^ (fig. 2, d), which extends inwardly 

 as the roof of the external auditory meatus. 

 It is partially defined from the temporal ridge by 

 a variable, irregular crescentoid indentation. '' 

 The inner extremity defines the meatus from the 

 tj'mpanic cavit\' bj' an acute curved edge, from 

 which a wide crescentoid plate, the tympanic 

 scide,^ slants upward, and forms the outer 

 boundary of the upper portion of the tympanic 

 cavity. The scute (fig. 1, &; fig. 2, c) can best 

 be seen by sawing the temporal bone fore and 

 aft throiTgh the tj'mpanic cavity, and viewing 

 the outer division of the bone from within. The 

 scute is scpciratcd externally' from the rest of 

 the auditor}' plate b^' spongj' substance, but 

 occasionalljr is continuous through thick, com- 

 pact substance. Its anterior border joins the 



* Lamina auditoria. 2 Post-auditory fossa. 



3 Scutum tympanicum. 



