582 Transactions of the Societij. 



unknown in Great Britain till 1907, when Southern (Irish 

 Naturalist, xvi. p. 70) added the following details : " Two specimens 

 of this worm were found. They were very small, 4-5 mm. in 

 length. Number of segments 34. Salivary glands were not 

 observed. Prostate gland very large. The brain is straight 

 behind, not concave as described. It is concave in front, and the 

 sides diverge backwards. The spermatheca (of which a figure is 

 given) consists of an oval ampulla, with an efferent duct twice as 

 long as the ampulla. The duct leading into the oesophagus is equal 

 in length to the efferent duct." In view of the fact that many new 

 species have since been added to the British list, it may be ques- 

 tioned whether Southern's record is rightly to be placed to the 

 account of H. dicksoni. Bretscher {4) and Issel {11) have made 

 notes on the subject ; and, while my own records suggest that it may 

 be a very variable worm, I am rather disposed to the conclusion 

 that closer definition and careful sifting are needed. If the records 

 are all reliable they prove that this species is by no means rare. 

 They are as follows : — 



British Records. — Lambay, Ireland (Southern, as above). 

 " Summit of Montpelier, co. Dublin ; Isle of Man, Port Erin " 

 (Southern, Contributions, p. 146). Stream at Netherseal, Derby- 

 shire, Autumn 1911. Length 5-6 mm. Segments 25. Adult. 

 Brain, slightly concave behind, about as long as broad, and con- 

 verging forwards. Seta? about 6 in front, Fridericia-lUkQ, and 4-5 

 behind larger and more equal. Spermathecie almost the shape of 

 a champagne bottle. Duct of nephridium about equals the post- 

 septal in length, and springs from near the middle. Four pairs of 

 large nephridia in 6/7-9/10. The dorsal vessel arising in 10/11. 

 It will be seen that this is different in many points from the type ; 

 and it may ultimately have to find a place elsewhere. The same 

 applies to specimens found at Hastings, December 21, 1911, and 

 PtoUeston Junction, Notts, March 26, 1912. 



4. Henlea hihernica Southern. 



A stout worm, greyish white and opaque. Epithelium glan- 

 dular, as is often the case. Length 15-20 mm. Segments 60. 

 Ventral seta^ 5-9 per set, lateral 5-7, slightly curved and of unequal 

 lengths. Brain longer than broad, slightly convex in front and 

 emarginate behind. Salivary glands long, twisted, lying on the 

 ventral surface of cesophagus. Two oesophageal glands project into 

 8th segment. The dorsal vessel rises in the 8/9 intersegmental 

 groove, and has three contractile swellings in segments 6-8. 

 Sperm funnel 3-4 times as long as broad, with parallel sides and 

 a fairly long duct. Spermatheca pear-shaped, duct sharply defined, 

 small glands frequent at the opening in 4/5. It differs from H. 

 nasuta, which Southern regarded as its nearest ally, in the number 



