NOTES AND MEMORANDA. 91 



Muraena helena. Linn. A fine specimen was brought to the 

 Laboratory on March ord, 1897, with the information that it was 

 trawled off the Eddystone, and was just alive when brought on deck. 

 It measured ■44-6 inches, or 113'4 cm., and proved to be a male with 

 ripe testes, the milt readily exuding on pressure. The spermatozoa are 

 rather large, but were not measured. 



In view of the known existence of sexual dimorphism in the family, 

 the following measurements may be of interest : — 



Total length . . . .113-4 cm. 



Snout to anus . ... 54*2 „ 



„ gill opening . . . 14 „ 



„ angle of jaw . . . 6 „ 



„ eye . ... 3 „ 



Length of „ . . . . "8 ,, 



Interorbital space (horizontal) . . . 1'9 „ 



Greatest girth (at gill opening) . . . 26'8 „ 



Girth in front of anus . . . 23'6 ,, 



In colour the specimen resembled such Mediterranean forms as I 

 have seen, the orange of the anterior ventral region being much less 

 vivid and less extensive than in Couch's figure. The whole body was 

 very soft and flabby, and appeared distended, as though the tissues were 

 undergoing mucoid or colloid degeneration, but such proved to be 

 not the case. The marginal fins were almost entirely masked by the 

 skin and body tissues, the anal, in particular, so much so as not 

 to reach the general ventral surface level. The skin of the abdomen 

 was exceedingly tough, and about '5 cm. thick. It consisted of an 

 outer white layer, hard and consistent, and a much thicker inner portion, 

 somewhat gelatinous in character. The testis was long and baud-like, 

 somewhat crenulate behind. It terminated a little behind the vent 

 posteriorly, extending forward at least half-way along the abdominal 

 cavity. A round wound, about two inches in diameter, and probably 

 caused by a dog-fish, was present on the left side of the tail, involving 

 the loss of the skin and underlying muscles. 



Only two records of the occurrence of this fish in British waters 

 have come under my notice, viz., from Polperro and Fowey (Couch). 

 The only specimen measured was just two inches shorter than the 

 Plymouth example. — E. W. L. H. 



