British Enchytreeids. By Rev. H. Friend. 597 



,, I Dorsal vessel arises in intersegment 8/!) . . H. arenirol a {10) 

 (Dorsal vessel arises in segment 9 — 10 



-|Q I Characters very variable H. variata (IQ) 



' I Characters fairly constant — 11 

 ,. ) Small : length 2-3 mm., segments 30 . . II. jMrpnsiUa (8) 



■ (Larger : length 10-12 mm., segments 40-50 H. rhsetica (18) 

 -..^ I One pair oesophageal glands — 13 



"■ (Two pairs oesophageal glands H. ventricidosa (2) 



,o ICEsophageal glands in segment 7 — 14 

 (CEsophageal glands in segment 8 — 16 

 , , I Dorsal vessel arises in intersegment 7/8 — 15 



■ (Dorsal vessel arises in segment 8 . . . . H. nasnta (1) 



^. I Small attenuated form H . attenuata {11) 



'■( Larger and more robust H . heterotropa {Wj 



,^ I Dorsal vessel arises in 8/9 — 17 



■ (Dorsal vessel arises in 12/13 H. triloba {\^) 



(Sperm-funnel twice as long as broad — 18 



17. ] Sperm-funnel three or four times as long as 



I broad H. hibeniica (4) 



-r, J SpermatheciB with glands at 4/5 .... H. f rider icio ides {11) 



' ( Spermathecse without glands at 4/5 . . . H.fragilis (13) 



It may be interesting and helpful if we present a few of the 

 facts relating to the British species of the Henlca in another way. 

 Thus : all the species save one possess one pair of spermathecae 

 only, opening into 4/5. The exception is H. 'puteana, which has 

 two pairs opening into 3/4 and 4/5. This is so far unique, not 

 only for the genus but for the whole family of Enchytrteids. The 

 remainder fall into three groups : — 



1. Henlcas without resophageal glands. 



2. Henlcas with one pair of cesophageal glands. 



i. Occurring in segment 7. 

 ii. Occurring in segment 8. 



■3. Henleas with two pairs of resophageal glands. 



As only one species is at present known in group 3, there are 

 ■seventeen species to be allocated to groups 1 and 2, and these 

 again fall roughly into four sets, as follows : — 



1. No oesophageal glands. 



i. Setie not exceeding 5 per bundle (Xos. 1-4). 

 ii. Setae exceeding 5 per bundle (Nos. 5-10). 



2. One pair of oesophageal glands. 



i. Glands in segment 7 (Nos. 11-13). 

 ii. Glands in segment 8 (Nos. 14-17). 



