230 Miscellaneous. 



54^ inches. After being immersed for some time in spirits (the 

 specimens arrived dry and twisted round a piece of stick), they pre- 

 sent the appearance of a twisted piece of copper wire, indistinctly 

 striated across, and with a dark streak running down the centre 

 throughout its whole length. This Gordius feels to the touch ex- 

 ceedingly slippery, like a piece of recent sea-weed. It is slightly 

 more attenuated at the anterior than the posterior extremity. In all 

 probability it is of a cylindrical form like other Gordii ; but, owing 

 to the way in which it was sent to this country, it is at present of a 

 rather flattened form. 



I have named it Gordius fulgur from its native name of Lightning- 

 Snake. 



Hah. Forests of Batchian ; probably a native, in its immature state, 

 of some large insect. 



Order Cestoidea. 



5. Tetrabothrium Gerrardii. 



The genus Tetrabothrium was indicated by Rudolphi in his 

 * Synopsis Entozoorum,' for containing those species of Bothrioce- 

 phalus which possess four bothria. It was afterwards fully adopted 

 and characterized as a distinct genus by Diesing ; and nine species are 

 described by him. These were discovered all inhabiting the intestines 

 of certain Mammalia, Birds, and marine Fishes ; but none of them 

 have been, till now, recorded as living in Reptiles. 



The species now to be described, however, was found, by Mr. 

 Edward Gerrard of the British Museum (to whom I am indebted for 

 an opportunity of describing several new species of Entozoa), in the 

 intestines of a Boa constrictor from South America. 



The head is large, tetragonal ; the four bothria disposed cross- 

 wise, joined by the margins ; each of them large, round, and having 

 on one side a strong ridge. Body depressed, narrow, articulated. 

 No distinct neck. Anterior extremity of body very narrow, and the 

 articulations there are extremely small, becoming larger as they de- 

 scend, the inferior being quadrangular and rather large. The margins 

 of the articulations somewhat annulated, but having no appearance of 

 genital apertures. The head is about three-fourths of a line broad ; 

 but I could not discover any mouth. Apparently only fragments of 

 these worms were obtained ; but some of these detached pieces were 

 about 18 inches in length. 



Hub. Intestines of Boa constrictor. 



MISCELLANEOUS. 



On the Occurrence of Polar Species of Marine Crustacea in the 



Wettern Lake, Sweden. By Prof. Liljeborg. 



To the Editors of the Annals of Natural History. 



Gentlemen, — In a letter that I have recently received from Prof. 



Liljeborg, among other information, the following passage occurs, 



