84 



G. J. de Fejervary: 



fine examples illustrating some important points with respect to 

 the formation (phase of ascension) and c u 1 m i n a t i ng de velopment 

 of the treated dermal ossifications. 



Before terminating this brief sketch of the secondaiy dermal 

 ossifications in the Lacertilia, I should like to draw attention to 

 some spare literary references regarding this subject. 



As far as I am informed, Mr. Calori was the first who, in 

 1858, discussed the ,,scudetti o squame ossee cutanee" occurring 

 on the Saurian skull. According to this author these bony scutes 

 are ,,cosi saldate alle ossa sottoposte che non vale ingengno, ne 

 destrezza a sollevarle, e formano sopra quelle ossa come una 

 incrostazione."27) 



A few years later Prof. Leydig^^) also deals with the ,,crusta 

 calcarea" of Saurians. He very judiciously recognized its (corial) 

 genesis, and refers to it under the term of Verknöcherte Schädel- 

 haut". He also recognized the difference which exists between the 

 lamina supraciliaris and the temporal armour on one hand, and the 

 other bones constituting the roof of the skull on the other. As 

 regards the supraciliary lamina and the temporal armour, Prof. 

 Leydig writes as follows: Ferner aber gibt es . . . echte für sich 

 bleibende Hautknochen, welche nicht mit einem aus der häutigen, 

 embryonalen Schädelwand entstandenen Knochen verschmolzen 

 sind." — He seems to make a difference between the ,,calcareous 

 crusta" and the independent echte . . . Hautknochen" just 

 referred to, and though, as stated above,^^) this difference is not 

 a meritorious one, it is.but a quantitative andnot qualita- 

 tive difference, the dependency or in dependency of these 

 secondary dermal ossifications being, as already mentioncd, 

 merely due to their different topographical conditions. 

 On p. 49 we find the following Observation: ,,Die Knochenkruste 

 am Schädel erhält eine fernere Bedeutung für uns dadurch, dass 

 sie es ist, welche durch ihre grosseren Gefässfurchen die Abgrenzung 

 der sogenannten Kopfschilder bedingt, letztere sonach keineswegs 

 ganz und überall mit dem Umriss der darunterliegenden Knochen 

 zusammenfallen." And further on: ,,Es genügt das Auftreten 

 einer neuen Gefässfurche, um ein Schild weiter zu gliedern oder 

 umgekehrt, es kann ein Schild, das sonst für sich besteht, bei 

 Mangel einer solchen Trennungsfurche in ein anderes aufgenommen 

 sein." It would lead us to far to enlarge upon the formation and 



2') L. Calori, Sulla Scheletografia de'Saurii. Nota II. Sullo Schel. 

 della Lacerta viridis L. Sulla riprod. d. coda nelle Lucertole e s. ossa cutanee 

 del teschio de'Saurii, Bologna, 1858. (Fide F. Siebenrock, D, Skelet d. 

 Lacerta Simonyi Steind. u. d. Lacertidenfamilie überhaupt, Sitzungsber. d. 

 Kais. Akad. d. Wiss. in Wien, Math, naturw. Cl., Bd. CHI, Abt. I, 1894, 

 p. 224). 



2«) Die in Deutschi. leb. Arten d. Saurier, Tübingen, 1872, p. 47 — 50. 

 ^''^) Cfr. the discussion of the secondary deimal bones and the crusta 

 calcarea, on p. 75 — 76. 



