Brachiopods in the Persian Gulf. 41 
(truncated) anteriorly. ‘The size of the specimen is :—Length 
15°7, breadth 13°5, thickness 7-4 mm. It is much depressed 
dorso-ventrally and exhibits incipient uniplication, possessing 
a broad but low dorsal fold and a very shallow sulcus down 
the ventral valve. It presents some slight resemblance to 
examples of 7. caput-serpentis from the Mediterranean named 
var. emarginata, Risso (=mediterranea, Jeffreys*), but is 
not notched anteriorly as in that form. The test is thicker 
than in recent specimens of emarginata ; the shell-surface is 
also more strongly striated, and possesses stronger and more 
numerous growth-lines. The striz are somewhat nodulose, 
especially posteriorly ; the lateral primaries diverge rather 
sharply near the umbo of the dorsal valve—a_ noticeable 
feature. The specimen differs from dredged examples of 
T. caput-serpentis from Oban, W. of Scotland, Trondhjem, 
Norway, and other North-Atlantic places by its flatness, by 
the early divergence of the primary striz, and by the strize in 
general not presenting the same fasciculate aspect. In this 
respect the specimen agrees better with the Mediterranean 
form. 
In 1908 Blochmann f created a new species—Terebratulina 
valdivie—for some specimens collected by the ‘ Valdivia’ 
Expedition in the Indian Ocean, off the 8. coast of Nias, at 
677 metres (=376 fath.). These specimens were originally 
considered and labelled as J’, caput-serpentis, but a later 
study of the spiculation of the animal furnished good evidence, 
together with a characteristic difference in the construction of 
the brachidium, that a new species was represented. Bloch- 
mann, unfortunately, gives no figure of the shell, and his - 
description is on the whole very meagre. He merely states 
that it agrees in general appearance with the Mediterranean 
form of 17’, caput-serpentis, but is a little flatter and wider. 
‘Lhe absence of the animal and the imperfect condition of the 
brachidium in the Dabai specimen are to be regretted, as a 
comparison with JZ. valdiviw, based on these characters, is 
not possible. Blochmann, in comparing the spiculation of 
T. valdivie with TZ’. caput-serpentis, unfortunately made use of 
Norwegian examples of the latter instead of Mediterranean 
specimens, so that the precise relationship between the 
Mediterranean and Indian-Ocean forms is somewhat uncertain. 
‘There issome probability that 7. valdivie, the Dabai form, 
* Davidson, “ Monograph of Recent Brachiopoda,” Pt. I., Trans. Linn, 
Soc. Lond. 2nd ser. vol. iv., Zool. 1886 (p. 25 reprint), pl. v. figs. 35-37. 
+ Blochmann, “Zur Systematik und geographischen Verbreitung der 
Brachiopoden,” Zeit. fiir wiss. Zoologie, Bd. xc. 1908, pp. 606-607 
(spicula figured, pl. xxxvi. figs. 5, 6). 
