Boros István (szerk.): A Magyar Természettudományi Múzeum évkönyve 2. (Budapest 1952)

Szunyoghy, J.: The effect of castration on the skull of the domestic cat, and the establishment of differentiating characters on the skulls of the domestic cat and the wild cat

Blasius takes as a differentiating key the site of Pm

1, the position of the tubercles on Pm

2, the backward extension of the caudal ends of the nasal bones in relation to the mandible, the separation of the frontal and temporal bones by the processes of the parietal and sphenoid bones, and the form of fissura palatina ; Ogne v the form of the nasal bones and the contacting trend of the processus zygomaticus ossis frontalis with the processus frontalis ossis zyfeomatici, the situation and form of the orbitals, the form of the. auditory bullae. All these characters are, however, inconstant and are not reliable for an indubitable separation. A. and G. Zimmermann write on page 5 of their work that »there are several osteologic differences between the two species. So the skull of the wild cat is longer, its nasal bones are truncate on their caudal ends, while in the domestic cat the caudal ends of the nasals shraply wedges into the frontal bones. The frontal bone meets with the temporal bone in the wild cat, while in the domestic cat the temporal alae of the parietal and sphenoid bones wedge between the two«. This statement of above authors needs proving. As it is, craniometric data confirm that the skull of the wild cat is not longer but shaped similarly with the domestic cat.

2 Tljeri the caudal ends of the nasal bones wedge sharply into the frontal bones in both species, so they evidently cannot be truncate in the wild cat. Also their assertion that the frontal bone directly meets with the temporal bone in the wild cat needs rectification. ín examining 19 wild cat skulls I found that the temporal wing of the parietal and sphenoid bones wedge between the frontal and temporal bones (like in the domestic cat) in 14 cases, while with the direct fusing of the frontal and temporal bones on both sides I met with only once, above fusion occurring in the remaining four cases on one side of the skulls only, and here, too, only along a line of 1 to 2 millimetres. Therefore this character is also unsuitable for a distinct separation of the two species. Let us see then the differences that really distinguish the skulls of the two species : 1. A morphologically essential deviation seems to be (at least as my examined material shows) the profil. This is much more protuberant because of the well developed tuber frontale of the frontal bone in the wild cat than in the domestic cat (T. II. 5., 7., 8.), where the tuber frontale of the frontal bone is only characteristic of juvenile and semiadult skulls, as the frontal surface becomes plain in more mature years. My opinion corresponds with S'atunin's, who states that the frontal part of the wild cat's skull is essentially archer while the frontal bone is almost totally plain and well nigh rhombic in form in the domestic cat. 2. There is a distinct difference also in the zygomatic arch. This seems to run parallel with the main axis of the skull (viewed from above) in the domestic cat, broadening out caudolaterally more in. the wild cat, so that the place confined by the zygomatic arches becomes cordiform in the latter case (T. I. 1—4, II. 6.). 3. One of the chief characters of the domestic cat's skull is the diameter of the zygomatic arch in its most narrow point (T. II. 5.), the limitations being 9,5—15,5 mms in the domestic cat, and 9,4—11,8 mms in the wild cat. This difference in size becomes more pregnant when compared with also the limit values of the condylobasal length : 72,5—90,2 mms in the wild, and 65,2—79 mms in the domestic cat. This proves that the height of the zygomatic arch in relation to the condylobasal length is distinctly greater in the domestic cat than in the wild one. 4. A further character is the inflation on the caudal ends of the nasal bones in the domestic cat, lacking or present in marks only in its wild relative. This difference is more distinctly visible in young specimens (T. I. 1,3, III. 9—10).' 5. Another character seems to be the form of the processus zygomaticus of the frontal bone, which is rather broader in the domestic cat as against the narrower one in the wild cat (T. II. 5., 7., 8.). 6. I left till the last the stronger dentition of the wild cat. In the case of similar wild cat and domestic cat skulls the size, strength, and sharpness of the canine, molar, and especially incisor teeth will determine the specific problem (T. III. 11—16.). 2 Though, indubitably, there can be found a shorter skull form, especially in the case of the domestic cat. 12* 179