1870.| DR. MURIE ON AN GSTRUS FROM THE HIPPOPOTAMUS. 77 
III. The beak of the skull from the notch rather shorter than from 
the notch to the condyle, depressed, flat above, gradually 
tapering in front; the width at the notch two-thirds of the 
entire length of the beak. Lower jaw slender, narrow and 
thin in front. FERESA. 
§. Orca INTERMEDIA. 
Orca intermedia, Gray, Cat. Seals and Whales, p. 283; Zool. 
Erebus and Terror, p. 34, tab. 8 (skull). 
Hab. ? 
This is the skull of a very small species of the genus. It is 
evidently one of a full-grown animal, and yet it is not so large as the 
skull of a newly born specimen of the other species. Mr. Flower, 
judging from the figure, believed it to be the skull of a very young 
animal; but on examining the skull along with me he became satis- 
fied, from the solidity and definite form of the bones, that it is the 
skull of a full-grown though not aged specimen. 
This skull has many resemblances to the skull of some of the 
species of Electra; the teeth are much smaller than those of Orca. 
The following are the measurements of the different skulls of the 
genus in the collection of the British Museum; they are carefully 
taken with calipers by Mr. Edward Gerrard. 
















O. stenorhyncha. hips saa O. pacifica. packed 
3616. | d6le. |1065d,¢.| 361 a. 1065 a. 362 a. 
7 Ee site i in. lin.) in. lin.} in. lin.}in. lin.| in. lin. | in, lin. 
en rom end of nasa or & : “ 
Eatin of occipital condyle iSO OBA s0H83 VO) B65 By deed 
Length of nose ............ 17 6/18 6/22 6117 0} 18 0 | 7 O 
of tooth-line ........ 13 6/14 0/16 0/138 O} 14 6 | 4 9 
of lower jaw ........ 27 6)30 0/31 0/26 O| 29 6 }1l 38 
Breadth at the notch ....... 10 6/11 O}12 0/10 O; 12 6} 4 9 
at the orbit ........ 18 0;19 6/20 0/18 O}; 21 0] 8 6 
—at temple above ..../18 0/19 6/20 0/18 0} 20 0] 9 O 
—at middle of beak....| 9 0);10 O}11 0} 9 6) 10 0] 3 6 
—-—— at intermaxillaries ..| 3 3] 3 3/ 4 6} 3 3] 3 6] 0 9 


——_—s— 
7. On a Larval Gstrus found in the Hippopotamus. By 
James Muriz, M.D., F.L.S., F.G.S., &c., Prosector to 
the Society. 
Neither in the comprehensive ‘ Monographie der Mstriden’ of 
Frederich Brauer (Vienna, 1863), nor in the writings of others who 
have treated of species of the Gstrid family of Diptera, in the larval 
or imago state, do I find any mention that the Hippopotamus occa- 
sionally serves as a nidus for the immature insect. For this reason 
I place the following observation of such a case on record. 
A number of the orders of Mammalia are subjects whereon or 
