140 NEW BRITISH WORM. 



in the discoverer. Agreeably to the invitation of Dr. Benham, of 

 University College, London, published in the Field newspaper, we 

 forwarded parcels of worms for his inspection and determination. 

 Amongst these were some small worms, about an inch in length, 

 found beneath the stones of the gravelly bed of a stream at Hyde, 

 near Bloxworth. These proved to be of a different genus to the 

 ordinary earthworm, the genus and species not having, up till then, 

 been recorded as occurring in Great Britain. As Dr. Benham 

 wished to ascertain whether they were really aquatic worms or not, 

 we took some trouble in determining exactly where and under what 

 conditions this interesting worm occurred, with the result that the 

 worm was pronounced semi-aquatic. It always occurred below high 

 water mark, and seemed in no way inconvenienced when totally 

 submerged, as we often found them under the stones 3 or 4 inches 

 below the surface. 



The name of this worm is " Allurus tetraedrus." The position 

 of the four pairs of bristles with which each segment is provided 

 and the position of the genital organs seem to be chief points to be 

 noticed in determining the genus and species. Another small 

 worm, " Allolobopliora Boeckii" was found in some abundance in 

 the wet bed of a marshy swamp at Morden Park. These, too, are 

 interesting from the fact that the bristles, instead of being arranged 

 in four pairs, are arranged as eight almost equidistant and single 

 bristles. Those of the ordinary worm, " Lumbricus terrestris," are 

 in four pairs, and confined to the ventral surface. Those of " Allurus 

 tetraedrus " are in four equidistant pairs, each pair forming the angle 

 of a square when viewed in transverse sections. (See diagrams.) 



The aquatic worm, " Allurus tetraedrus" was found, soon after its 

 discovery in Dorsetshire, in a stream not far from London, and we 

 have just now, December 6th, found it also in Essex, living under 

 conditions similar to those under which they were discovered in 

 Dorsetshire. 



Dr. Benham is about to publish a Monograph on British earth- 

 worms, and doubtless the new worm will be duly honoured with a 

 figure and description in that work. 



