580 Transactions of the Society. 



of the species, to be described hereafter, show a distinct breaking 

 away from the old generic bonds. One seems to have four pairs 

 of septal glands, two or three species reveal the origin of the dorsal 

 vessel in the girdle segments, like certain species of Lumhricillus, 

 and at least one species has the cesophagus gradually merging in 

 the intestine. And yet the main characters are Henlean. In the 

 majority of cases the brain has a distinctive shape and size, 

 differentiating it at once from such a genus as Frideinria, which it 

 often closely resembles in the matter of setae. The ccelomic 

 corpuscles, also, which IMichaelsen speaks of as large and discoid, 

 are very often quite Unchytr/ims-like in character. Thus it is 

 apparent that at present our boundary lines cannot be very 

 definitely laid down. 



III. — Systematic Survey. 



In enumerating and describing the sjiecies of Henlea at present 

 known to occur in Great Britain, I propose to follow a chrono- 

 logical order. We shall by this means obtain an accurate idea of 

 the way in which our knowledge of the genus has grown, while 

 the systems of classification which will be appended may be used 

 by those who wish readily to determine such species as they may 

 have to identify. 



1. Henlea na.suta. Eisen. • 



The living worm is white or yellowish, 15-20 mm. in length 

 with 50 to 60 segments. The innermost seta? in the anterior 

 bundles are often of unequal lengths, as in Fridericia, and usually 

 number 4-7 per bundle. The brain is about as long as broad, or a 

 little longer, the hinder part being more or less incised or concave. 

 The ccelomic corpuscles are discoid or broad oval, and pepto- 

 nephridia or salivary glands are present, sparingly branched. The 

 oesophagus goes suddenly into the intestine at the posterior end of 

 the 7th segment, and the dorsal vessel arises in the 8th. Here 

 will be found a pair of cesophageal glands. The spermathecae open 

 in the intersegment 4/5 without glands, and the ampulla is about 

 twice as long as the duct. Such are the leading characteristics as 

 set forth by Michaelsen. In this instance my own observations 

 do not enable me to make many additions to the diagnosis. In the 

 Irish specimen recorded by Southern, each segment had several 

 rows of irregular epidermal glands, giving the worm a dark aj)pear- 

 ance. The synonymy is fully given by Michaelsen, Das Tierreich, 

 X. p. 69. It appears as Henlea U'ptod.era Vejd. in Beddard and 

 elsewhere. This species has been found in Siberia, Germany, 

 Bohemia, Italy, France, England, Ireland, and Denmark. 



British Records. — I first discovered H. nasuta in May 1892, 

 between Idle and Woodhouse Grove, in Yorkshire. The Naturalist, 



