ANNULATA. 233 



testes ; STEENSTRUP on the contrary thinks that they ought not to be 

 considered to be the parts where the seed is formed, but where it is 

 collected (as seminal vesicles in the male subject, as bur see copulatrices 

 in the female). The efferent ducts of these vesicles open externally, 

 according to SAVIGNY ; but later writers have failed to discover the 

 openings ; rather are they in connexion with the efferent ducts of 

 the yellow saccules ; these ducts fall at length into a common canal 

 011 each side backwards and end with two openings at the fifteenth 

 or sixteenth ring of the body. At the origin of these two canals lie 

 two small irregular saccules, covered by a thin and glistening mem- 

 brane, which according to DUGES and STEENSTRUP are filled with 

 many convolutions of the efferent canal and form the passage of the 

 yellow saccules to the straight part of the canal which runs back- 

 wards \ Earth-worms are oviparous, not viviparous ; they pair 

 during the whole Summer, especially by night, when they creep 

 from the earth ; but how impregnation is effected, is not yet suffi- 

 ciently explained, since the apertures of the sexual organs are not 

 brought immediately together. The anterior portions of the two 

 worms lie next each other, but with the heads in opposite directions 

 (see in MOREEN 1. 1. Tab. xxvn). Thus the part named by WILLIS 

 Clitellum (saddle) in each of the two worms lies towards the place 

 where the sexual openings of the other worm are found. This cli- 

 tellum is a round swelling of the body which occupies from six to 

 nine rings (in Lumbricus agricola from the 29th to the 36th or from 

 the 31st to the 38th ring), and which during the time of copulation 

 is more strongly developed, and in young individuals is entirely 

 wanting. 



Sp. Lumbricus agricola HOFFM., Lumbricus terrestris L. (in part), HOFF- 

 MEISTER Die bekannte Arten aus der Fam. der Regenw. fig. i ; the largest 

 species in northern Europe, from eight inches to more than a foot in 

 length. 



Family V. Maldanice SAV. Branchiae none. Month bilabiate, 

 inferior. Kudiments of feet provided with setse ; the three anterior 

 pairs without ventral pinna, the rest with a transverse tubercle, 

 supplied with uncinate setse, in place of a ventral pinna. 



Clymene SAV. Body cylindrical, with few elongate segments, 



1 The best description and figure of the organs of propagation in Lumbricus were 

 given by G. R. TREVIRANUS, Zeitsch. fur Physiol. v. s. 154 166, Tab. in. ; see also 

 STEENSTRUP, Hermaphroditismus Tilvcerelse, pp. 35 40, Tab.i. figs, i 7, and H.MEC- 

 KELin MUELLER'S Archiv. 1844, 8.480 483. 



