370 Mr. E. W. L. Holt on the 
postlarval condition is reached. The month is from the first 
widely open and the eyes a brilliant silvery blue, the newly 
hatched herring being thus in advance of its ally the sprat. 
For the first few days of its life the herring is unable to 
rise from the bottom, lying on its side and occasionally lashing 
out with its tail; and even when able to rise it seems to keep 
near the bottom for some time, larval and early postlarval 
forms being taken together in great abundance in the bottom 
trawl-net used at this laboratory on the 380th March, 1889. 
The postlarval herring is very voracious, not disdaining 
cannibalism, whilst it is preyed on doubtless by larger fishes. 
The growth of the herring is at first slow, there being an 
increase of about 3‘; inch in the first ten days of free life. 
Becoming more vigorous, the postlarval herrings ascend 
into midwater ; specimens (fig. 2) 7 inch long were taken 
with the midwater-net on March 22, 1889, being thus some- 
what earlier than their fellows. ~*~ 
At this length the permanent dorsal fin is clearly indicated, 
the cartilages of the hyoid and branchial arches are well 
developed, the pectoral fins are pediculate, the tail shows an 
indication of the heterocereal condition. The continuous 
embryonic (median) fin is still retained ; the maxille are well 
developed, and bear sharp-pointed teeth on their anterior 
edges. 
On April 14, 1859, the herrings were still in midwater, a 
little over half an inch in length; the embryonie median fin 
was nearly or quite lost, and the hypural elements of the tail 
were well marked. 
Pigmentation * other than that of the eyes appears before 
the postlarval condition is reached and is retained unchanged 
for a considerable period. It is entirely black, and consists 
of one or two median chromatophores below the heart, a chain 
of about ten chromatophores commeneing behind each pectoral 
fin and running backwards on each side of the gut for about 
half its length; an irregular, sometimes double, chain ventral 
to the posterior half of the gut ; two (sometimes one) stellate 
* Cf. Prof. M‘Intosh and E. E. Prince, “ Development and Life- 
histories of Food-fish,” Trans. R. 8. EF. vol. xxxy. 
