ON AMPHILINA PARAGONOPORA 51 



tissue attaching the bladder to the dorsal muscles and vertebral 

 column. Another Amphilina, 200 mm. long, was found to 

 have bored through the wall of the gas bladder into its cavity, 

 half the worm being in the cavity and half still outside, and 

 another large Amphilina was found to be buried in the muscles 

 of the body-wall anteriorly. A. paragonopora is also 

 occasionally to be found on the external surface of the fish, 

 and my attention was first drawn to the parasite by discovering 

 part (56 mm. long, and a portion anterior to this, including the 

 proboscis, of unknown length, had become detached) of 

 a large specimen emerging from a perforation at the base of 

 the left pectoral fin and lying on the outside of the skin (PI. 3, 

 tig. 3). On cutting open the perforation I found that a further 

 portion of the worm (34 mm. long) lay in a cavity in the muscles 

 of the body-wall, and that the remainder of the worm (the 

 hind portion, 40 mm. long) lay inside the body-cavity. This 

 Amphihna, therefore, had evidently bored its way through 

 the body-wall in the neighbourhood of the base of the left 

 pectoral fin (where the body-wall is very thin), and, had it not 

 been caught in the act, would doubtless have altogether 

 escaped from the fish. The uterus of this Amphilina (130 mm. 

 in length plus an unknown length of anterior portion detached) 

 was full of nearly or fully mature larvae (PI. 4, fig. 35). In 

 another fish also I found a small worm (only 11 mm. long) 

 lying on (not attached to) the surface of the external skin just 

 behind the anus. I cannot say whether or not this worm had 

 escaped from the body-cavity of this fish, but it is possible 

 (although the worm was of course immature sexually) since 

 in this fish a large perforation (some 3 mm. in diameter) was 

 found at the base of the right pectoral fin, leading into a large 

 inflamed cavity in the body-wall and thence into the body 

 cavity. Out of fifty-one ^ Ma crones aor and M . s e e n - 

 ghala, most but not all of which I specially examined for 

 perforations under the pectoral fins, seven were seen to 

 possess these perforations (situated either under the left 



^ In all I examined during this inquiry about one hundred specimens 

 of Mac rones ,sp., in twenty- two of which I found active Amphilina. 



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