A KEY TO BRITISH HENLEAS. 83 



been discovered since my latest reports were published. A very 

 careful revision of the whole of my material during the month of 

 February showed that no fewer than twenty-nine species may 

 now be regarded as British. Henlea variata, Friend, is proved 

 to be the same in all essentials as H. rhcetica, Bret., whose 

 description must be extended to admit our native specimens. As 

 no fewer than two out of every three of our indigenous species 

 are destitute of oesophageal glands, it is proposed to divide the 

 material into two groups, and retain the name Henlea for the 

 one, adopting that of Henleanella for the other. 

 Subjoined are the descriptions of new species : — 



1. Henlea alba, sp. nov. 



Length when alive 12-15 mm. Segments 50. Transparent, 

 white. Three pairs of septal glands in the normal positions. 

 Setae 3-4 in the lateral, and 4-5 in the ventral bundles. Sper- 

 mathecae with ampulla or bulb midway between the two ends of 

 the duct. No glands at the 4-5 opening. The normal salivary 

 glands wanting, but a pair of nephridia-like bodies (or apparently 

 three) between the second and third pair 'of septals. If these 

 are cesophageal glands they are abnormal in position and 

 appearance. Similar glands are found in H. inusitata, and 

 Bretscher has drawn attention to a like anomaly in H. gubleri. 



Girdle as usual extending over segment 12 to the setae of 13. 

 Ccelomic corpuscles of the brown, horny type so characteristic of 

 several species of Henlea. Chloragogen cells large. The pre- 

 clitellian nephridia found only in three segments, 8-9, 9-10, 

 10-11 ; but they often vary in number and position in different 

 species. The dorsal vessel arises in the girdle, or in segment 

 13-14, where the intestine enlarges. No other species of 

 Henlea has hitherto been found with the vessel in so backward a 

 position, though it is frequent in Enchytrceus and Fridericia. 

 The oesophagus goes gradually into the intestine behind the last 

 pair of septal glands, where the bulb usually occurs. 



Collected at Netherhall, Bretby, Derbyshire, November 22nd, 

 1912, near an old tree-stump. 



2. Henlea inusitata, sp. nov. 

 Length 6-10 mm. Segments 30-35 ; white and transparent. 



Setae 3-6 behind, 5-8 in front in the lateral bundles, sometimes 



h2 



