162 ZOOLOGY OF THE VOYAGE OF THE BEAGLE. 
rather the longest ; neither can I discern any teeth on the palatines, though there 
is a patch of very minute ones in front of the vomer. 
That this species really belongs to Aphritis, would seem indicated not merely 
by the aggregate of its external characters, but by the internal structure also, which 
was examined in one of the two specimens brought home by Mr. Darwin, and 
found conformable to what is stated by Valenciennes, in this respect, of the 
A. Urvillii. The stomach is large, with four very distinct coecal appendages, 
and there is no air-bladder. 
The A. undulatus, which I have so named in reference to the undulating 
longitudinal lines on the sides, is very Cypriniform in general appearance, and 
not altogether unlike the common minnow, Cyprinus Phowxinus. 
2. APHRITIS POROSUS. Jen. 
A. brevior: pallide olivaceus, lateribus fasciis transversis obsoletis nigricantibus ; 
pinnis omnibus brunneis: maxilla inferiore, et limbo preoperculi, poris conspicuis 
circiter novem, suborbitalibus circiter quinque, seriatim dispositis. 
D. 8—25; A. 1/22; C. 14, &c.; P. 23; V. 1/5. 
Lone. unc. 2. lin. 5. 
Form.—Not so much elongated as the last species: the depth rather more than one-sixth of the 
entire length, and the head only four times in the same. Also distinguished by a row of large 
mucous pores on the lower jaw, passing upwards posteriorly, and continued along the limb of 
the preopercle: the number of these pores on each side js nine or ten: a row of similar pores, 
amounting to about five, passes backwards from a little above the end of the maxillary beneath 
each eye. In other respects, the form is similar to that of the last species, excepting that the 
interval between the second dorsal and the caudal is only one-eighth of the entire length, in 
consequence of the body being less elongated. 
Cotour.—(In spirits). Back and upper half of the sides, olivaceous brown; beneath silvery. No 
very obvious markings; but traces may be seen of six or seven transverse dusky fascie, 
reaching from the back to a little beneath the lateral line, which were probably more distinct 
in the recent state. All the fins brownish ;.the dorsal a little powdered with dusky specks. 
The fourth and fifth rays of the ventrals are white, and appear to have been always of a 
different colour from the rest of the fin, 
Habitat, Coast of Patagonia. 
This appears to be another new species of Aphritis, taken by Mr. Darwin on 
mud-banks, in Port Desire, central Patagonia. It is very closely allied to the 
A. undulatus, but, I conceive, certainly distinct. There is but one specimen in 
the collection. 
