50 



Part III. — Twenty-eighth Annual Report 



Two congers examined in September measured 4 feet 4| inches (131 cm.) 

 and 4 feet 5| inches (134 cm.) respectively. The larger specimen was 

 the darker in colour, and its flesh was not so firm as that of the small fish. 

 The ovary of the latter was small; the eggs were white and measured 

 •22 mm. in diameter. The larger fish had large ovaries, the eggs in which 

 varied from -25 to '55 mm. in diameter. 



The largest eggs obtained from the conger by Cunningham were opaque 

 white and measured 1-0 mm. in diameter. 



Eigenmann* has provisionally described a pelagic egg which was obtained 

 in the waters of the United States as that of Conger vulgaris. The egg. 

 measured 2'4-2*75 mm. in diameter, and was "very closely related to No. 6 

 of the Mursenoid eggs of Eaffaele," 



The Eggs of the Tusk (Brosmius brosme). 



Some fertilized eggs oi the Tusk were sent by Mr. Duthie, Fishery Officer, 

 Lerwick. They arrived on 12th May, 1905, and were examined next day. 

 A number were alive and floating. They measured 1*2 mm. (1), 1*22 mm. 

 (3), 1-25 mm. (14), 1-27 mm. (7), 1'3 mm. (1). The oil globule measured 

 •25 mm. in diameter. The stage of development was early, viz., blastodisc 

 stage, with the segmentation (or germinal) cavity formed (fig. 51). The oil 

 globule had a bronze colour. The development of this form has been 

 minutely described by M'Intosh,t and, so far as my own observations go, 

 they confirm that zoologist's description. As M'Intosh pointed out, the 

 zona is creased, and the oil globule may move freely through the yolk. On 

 May 15th, of six eggs taken at random, four showed the segmentation cavity 

 stage ; the remaining two had the embryo half round the yolk, or a little 

 further on. The dorsum of the embryo was covered with minute black 

 pigment spots. The temperature of the water on this date was 12*1° C. 



An embryo observed on May 16th had a great quantity of black spots 

 dorsally on the head, body, and tail, but massed mainly over the abdominal 

 region. There was a lumen in the gut, and the heart was visible, although 

 not yet beating. There was only black pigment present, and it was all 

 dorsal in distribution. 



On May 18th one embryo completely encircled the yolk. Large round 

 black pigment spots were scattered over the dorsum of the whole fish. The 

 heart was beating. The oil globule was still large. The temperature of the 

 water was 12-6° C. 



May 22 — Some eggs were found to have hatched to-day. In the larva 

 the oil globule is posterior, and is of a bright bronze colour. There are 

 brown-black bars on the little fish — viz., one on the head, a small one on the 

 pectoral region, and a large bar about one-third of the distance between the 

 anus and end of the tail. A jet-black patch on the tail is very marked. 

 The pigment on the trunk is fairly scattered, and stellate in some cases. 

 There are black pigment spots on the ventral half of the body posterior to 

 the anus, showing a slight concentration midway between the anus and the 

 large black bar of pigment. The eye is not black. 



On May 26th the larva had the following naked-eye appearance : — It 

 showed five black bars across its body. The big black eyes and black 

 pigment on top of the head form the first bar. The second bar is a big 

 black patch on the dorsum over the hind half of the yolk-sac. The third, 

 fourth, and fifth bars are on -the post-anal body. No. 3 is a jet-black patch 

 at about one-third of the length of the post-anal body. The fifth is a big 



* "The Age and Development of the Conger Eel." Contributions from the 

 Biological Laboratory of the U.S. Fish Commission, Woods Hole, Mass. Bulletin 

 for 1901, pp. 37-44. 



t "On the Eggs of the Tusk." Tenth Annual Report of the Fishery Board Jor 

 Scotland for 1891, Pt. III., p. 288. 1892. 



