32 PROCEEDINGS OF THE NATIONAL MUSEUM. VOL. 62. 
The alveolae of this rostral fragment as figured by Jaeger ® are es- 
sentially the same as those found in the skulls of true squalodonts. 
Joseph Probst * has suggested that the teeth discussed by Van Bene- 
den “ under the name of Squalodon servatum, belong to Squalodon 
catula. However, Probst drew his conclusions from the rostral frag- 
ment, with teeth in situ, described and figured by De Zigno * under 
the name of Sgualodon catulli. 
The anterior end of the presphenoid is exposed and forms a plug 
across the proximal end of the mesorostral channel in the skull of 
Squalodon calvertensis. If Lortet’s figure of Squalodon bariensis and 
Von Meyer’s figure of Arionius servatus are correct, the mesethmoid 
in these forms a partition separating the nasal passages externally 
and diminishes in thickness anteriorly, presumably sheathing the 
vomer for a short distance forward. At any event there is no in- 
dication of the presence a presphenoid plug at the proximal end of 
the mesorostral channel. 
According to Probst ** the type skull of Arionius servatus possesses 
alveolae unlike those found in the skulls of other squalodonts. In 
this article he compares the teeth found near Baltringen with the 
teeth of Squalodon zitteli from Bleichenbach-sur-Rott, Bavaria, but 
concludes they show more relationship to the Italian specimens. It 
still remains to be shown that there are two species of squalodonts 
in the sandstone formation in the vincinity of Baltringen. 
PHYSOTHERIUM SOTTERII Portis. 
Physotherium sotterii Portis, A., Mémorie della Reale Accad. delle Sci. di 
Torino, ser. 2, vol. 37, pp. 325-326, pl. 7, figs. 91-94, 1886. 
Type specimen.—Original description based upon a fragment of a 
jaw, with four teeth in situ. Type probably in the collection of the 
University of Turin, Italy. 
Type locality —F rom the marine deposits ‘‘dell’Astigiana,” proba- 
bly in the valley of the Andona River, Italy. Astiano‘’ or Upper 
Pliocene. 
Subsequent allocation—This species is based upon such poor 
material that accurate determination or comparison with the other 
described forms is impossible. Abel‘ states that this genus does 
“Jiiger, G. F., Ueber die fossilen Siugethiere, welche in Wiirtemberg aufgefunden worden sind, 
Stuttgart, pt. 1, pl. 1, fig. 28, 1835. 
43 Probst, J., Jahreshefte des Vereins fiir vaterl. Naturkunde in Wiirttemberg, vol. 47, pp. 49-67, 
pl. 1, 1885. 
44Van Beneden, P. J., Bull. Acad. Roy. Sci. des Lettres et des Beaux-Arts, Bruxelles, ser. 2, vol. 41, 
No. 3, p. 474, pl.—, figs. 4-5, 7-9, 1876. 
45Zigno, A. de, Mém. R. Istituto Veneto di Scienze, Lettere et Arti, Venezia, vol. 20, pp. 8-13. pl.—, 
figs. 1-3, 1876. 
46 Probst, J. Jahreshefte des Vereins fiir vaterl. Naturkunde in Wiirttemberg, vol. 47, pp. 52, 53, 
1885. 
47 Sacco, F, Catalogo Paleontologico del Bacino Terziario del Piemonte, Boll. della Soc. geol. Italiana, 
vol. 8, fasc. 3, p. 191, 1890. 
4 Abel, O., Mém. Mus. Roy. Hist. Nat. Belgique, Bruxelles, vol. 3, p. 53, 1905. 
