THE HAG OR MYXINE 575 



coast of America, etc. It lives in the mud at depths of 

 40 to 300 fathoms. It often hes buried with only the 

 nostril protruding from the mud, but it can swim gracefully 

 and rapidly in eel -like fashion in search of prey. It eats 

 the bait off the fisherman's long lines, and it also enters 

 and devours the cod, etc., which have been caught on the 

 hooks. According to some, the hag also bores its way into 

 free-swimming fishes, but the evidence is not satis- 

 factory. According to Mr. J. T. Cunningham, the young 

 animals are hermaphrodite, containing immature ova and 

 ripe spermatozoa, while older forms produce ova only. If 

 the same form is first functionally a male and afterwards 

 functionally a female, the term " protandrous her- 

 maphroditism " is justified, and Nansen corroborated 

 Cunningham's discovery, which is, however, disputed by 

 Bashford Dean. A somewhat similar " protandrous " 

 hermaphroditism is known elsewhere, e.g. in the Nemertean 

 Stichostemma eilhardii, in the aberrant Myzostoma, and in 

 the crustacean Cvmothoidae. Hag are said to spawn m 

 late autumn. Of the development and early history 

 nothing is known. 



Form, skin, and muscular system.— The body is eel- 

 like, measuring 15 to 24 in. in the adult. The colour is 

 pinkish, the red blood shining through an unpigmented 

 skin. There is a slight median fin around the tail ; beside 

 the mouth and nostril there are four pairs of sensitive 

 barbules. There are no paired fins. The cloacal opening 

 is near the posterior end of the body. 



The skin is scaleless, and rich in goblet cells, which 

 secrete mucus. There is also a double row of glandular 

 pits, partly embedded in muscle, and arranged segmentally 

 on each side of the ventral surface along its entire length. 

 Each opens by a distinct pore, and so much mucus is rapidly 

 secreted that the ancients said the hag " could turn water 

 into glue." This makes the hag difficult to grip, and its 

 function is doubtless in part protective. The mucus chiefly 

 consists of strange spiral threads which uncoil when 

 ejected from the sacs. 



The zigzag muscle segments or myomeres are traceable. 

 The rasping teeth are worked by a powerful muscular 

 structure, sometimes called a " tongue." A section 



