A SMALL COLLECTION OF AMPHIPODA FROM JUAN FERNANDEZ 83 
Masafuera, »under stones, 500 metres above sea level», S. P. E. No. 
ga7 127. Il;017i»:\ Two tubes. 
One tube contains about one dozen specimens, one male, the others appar- 
ently females. These average about 12 mm. in length. In the other tube 
there are several specimens, all small, about 4 mm. in length. 
Masatierra, sunder stones.» S. PE. No. 729. 31. VII. 17: 
Several varying in size from 4 mm. in length up to 8 mm. Young speci- 
mens, none of them having the second gnathopod subchelate and none bearing 
eggs. 
Masatierra, »among withered leaves.» S. P. E. No. 494. 7. IV. 17. 
Several varying in size up to 8 mm., none with subchelate second gnatho- 
pods nor bearing eggs. 
Masaticrka, sin a-brook.> 5S; PE. Noi 7240%.31. VII. 17: 
12 specimens, the largest 9 mm., two of them being apparently immature 
males. 
I have no hesitation in identifying all the specimens named above as 
belonging to O. chzliensts M.-Edw., a species already known from South 
America and from New Zealand. In New Zealand it is the commonest of the 
shore hoppers and is usually found under stones, etc. about high water mark, 
though under favourable circumstances it may sometimes extend a little 
distance away from the sea. It is well described by STEBBING in Das Tier- 
reich, Amphipoda (1906, p. 537), and the fully developed male can generally 
be easily recognised by the stout second antenna, by the large rounded tooth 
or lobe near the finger hinge on the palm of the second gnathopod and by 
the broadening of the meral and carpal joints of the fifth peraeopod and, to 
a little extent, of the fourth peraeopod. The species was collected at the Juan 
Fernandez Islands by the Challenger Expedition and both male and female 
specimens were very fully described and figured by Stebbing under the name 
O. selkirkt. Yhe male examined and figured by him was probably somewhat 
immature for the fifth peraeopod shows no broadening of the joints, and the 
second gnathopod has not acquired the final adult form. 
I think there is no doubt that O. serrulata Dana is a synonym of OQ. 
chiliensts M.-Edw. This is clearly indicated by his figure of the last peraeopod 
(pl. 58, fig. 7,1) which shows the broadened carpus usually met with in this 
species; the figure of the second gnathopod (fig. 7,1) though too small to be 
of much value, indicates the tooth near the finger hinge with the rest of the 
palm slightly convex; figure 7,k, showing the serrulate margin of the basal 
joint of the fifth peraeopod, applies well to O. chzlzenszs though the character 
is possessed by other species also. Moreover DANA’s specimens were collected 
at the »Black Rocks, in the Bay of Islands, New Zealand» where O. chilienszs 
is abundant. STEBBING (1906, p. 536) has adopted DANA’s name 0. serrulata 
for the species described as O. aucklandiae by SPENCE BATE but that species 
is well marked in the male by the raised ridges or corrugations on the peraeon 
segments, a character which is not found in O. chzlzensis. The second gnatho- 
