ENCHYTRAEIDAE 251 



brane within which the sexual cells are shed and undergo their development into sperm 

 morulae and spermatozoa. The four species here discussed are so closely related that 

 they must obviously go in the same genus ; but it is somewhat doubtful which this ought 

 to be. It seems to me that the condition of the testes in werthi and aesttiiim resembles 

 rather that of LumbriciUiis, in grisea that of Marionina (nothing is stated regarding the 

 testes of benhami, which we may perhaps infer to resemble those of werthi). I place the 

 whole group in the genus Marionina, however, because Michaelsen (after some hesita- 

 tion) decided to refer his species werthi to this genus. 



Genus Lumbricillus, Orst. 

 Lumbricillus lineatus (Miill.). 



Pachydrilus verrucosus, Ude, 1896, p. 3, pi., fig. 6 a, 6 b. 



St. 122. 14. xii. 26. Maiviken, West Cumberland Bay, South Georgia. Shore coll. (salt water). 

 A number of specimens; along with LmnhriciUus maximus. 



St. 166. 19. ii. 27. South-east point of Paul Harbour, Signy Island, South Orkneys. Shore coll. 

 A number of specimens ; along with Lumbricillus maximus. 



St. 189. 23. iii. 27. Port Lockroy, Wiencke Island, Palmer Archipelago. Shore coll. Several 

 specimens; along with Lumbricillus maximus and Marionina grisea. 



The species is the same as that previously recorded, under the name of Pachydrilus 

 verrucosus, by Ude from Tierra del Fuego (Ude, 1896). It is one of the commonest of 

 the shore Enchytraeids of British coasts, and is well known from other European 

 countries also, and from inland stations as well as from the coasts. It is a variable species, 

 and has consequently been described under many names (cf. Stephenson, 1922). 



In the specimens from Wiencke Island and from the South Orkneys the septal 

 glands are remarkably small. As is commonly recognized, these glands often or usually 

 consist in each segment (iv, v and vi) of a portion in close association with the posterior 

 septum of the segment and often appearing to be contained between the two lamellae of 

 the septum, and a forwardly projecting lobe on each side ventrally in the segment. In 

 the specimens just mentioned the septal portions of the glands are reduced to a few cells 

 only, between the two layers of the septa; the forwardly projecting lobes are also 

 reduced, but not quite to the same extent. In the examples from South Georgia, how- 

 ever, the glands are of large size. 



One of the most variable organs of this worm appears to be the male funnel ; in the 

 several descriptions of the species under its various names different proportions are 

 given for the funnel, from 2 to 9 times as long as broad. In worms from one locality in 

 Scotland I found the funnels from 2! to 6 times as long as broad (Stephenson, 1922), 

 while in those from another place the funnels in the intact worm might be as much as 

 9 times, but might contract, on teasing the worms to isolate the internal organs, to as 

 Httle as twice as long as broad (Stephenson, 191 1 (L. subterraneus)). In the present 

 specimens they appear to be in some cases 5 or 6 times, in others 8-10 times as long as 

 broad. 



A notable characteristic of the species is the presence of transverse rows of very 

 deeply staining (with haematoxylin) gland cells in the integument. 



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