14 Mr. O. Thomas on a new Species of 
Schizoporella acuminata, n. sp. 
(Pl. I. fig. 1.) 
Zoecia short, lozenge-shaped (somewhat irregular), flattish, 
quincuncially disposed, bordered by a smooth raised line ; an 
acuminate suberect extension of the cell-wall behind the 
orifice, the apex or peak of which is slightly bent forward, 
and occupied by a smooth somewhat nodular prominence ; sur- 
face thickly covered with minute punctures; orifice semi- 
circular, with a rounded sinus on the lower margin, contracted 
at the opening and expahded below, rim slightly thickened ; 
on one side, a little below the orifice, an avicularium, with 
pointed mandible directed upwards. Occiwm occupying the 
place of the acuminate extremity of the cell, large, rounded, 
deeply immersed, the opening the same as that of the cell, but 
larger than the ordinary orifice, closed by the opercular valve ; 
surface punctate. 
Loc. Off Curtis Island, a single colony incrusting another 
polyzoon. 
A remarkable form, distinguished by the elevated peak-like 
upper extremity of the zocecium. 
HrpporHoa, Lamouroux. 
Hippothoa distans, MacGillivray. 
Hippothoa flagellum, Manzoni. 
A species occurs very abundantly amongst the Bass’s- 
Straits dredgings, creeping over shells &c., which is undoubt- 
edly the H. flagellum of Manzoni. I believe that it is the 
form described by MacGillivray as H. distans; and if so, the 
latter name, as the older, must take precedence, 
[To be continued. | 
Il.— Description of a new Species of Alactaga from Mesopo- 
tamia. By OLDFIELD THOMAS, I’.Z.S8., British Museum. 
Tue type specimens of the species here described (a male and 
a female) were obtained durmg the Euphrates expedition of 
1835-37, and are now in the British Museum. They pro- 
bably represent the “ Dipus jaculus” of the list of Mammals 
of Arabia and Mesopotamia, given in the Appendix to Col. 
Chesney’s account of that expedition*, being, to a superficial 
observer, somewhat similar to the D. jaculus (Pall. et auct. nec 
* Vol. i. p. 728 (1850). 
