1G<) M ERISTIC VARIATION. [PART I. 



probably we shall be right in regarding the majority of these 

 variation- .1- Homujotic. 



Li M MKICUS. Throughout this genus there is normally a 

 single pair of ovaries, placed in the 13th segment, on the posterior 

 -u i lace of the septum between the 12th and 13th segments. The 

 following cases of supernumerary ovaries are recorded : 



97. Lumbricus turgidus : specimen having an extra pair of ovaries 

 in tin- 14th 1 segment. 



98. Specimen having an extra ovary on the right side in the 14th 

 34 fluent. 



99. L. purpureus : specimen having an extra ovary on the left 

 M<1'- in the 1 4th segment. 



In all these cases the extra ovaries were in size, form and 

 P"-ition like the normal ovaries. There was no extra oviduct or 

 rec.'ptaciilum ovorum, but the normal ovaries and oviducts were 

 present as usual. BERGH, R. S., Zeit. f. wiss. Zool, XLIV. 1886, 

 p. 3< ),s, note. 



*10(). Allolobophora sp. [partly = Lumbricus, the common Earth- 

 worm] : specimen having, in all, seven pairs of ovaries; viz. a pair 

 in the 12th, 13th, 14th, loth, 16th, 17th and 18th segments. Of 

 tlu >e all except the pair of the 13th segment are supernumerary. 

 Kach of these ovaries was placed on the posterior face of a septum 

 in the n-iial position. The three anterior pairs in shape, structure 

 ami portion closely resembled the normal structures. Of these 

 the most anterior were slightly the largest. The four posterior 

 pairs were smaller and resembled the ovaries of a very young or 

 immature worm, but on examination all were found to contain 

 "va. The normal pair of oviducts were present and no extra ovi- 

 ducts could lie found, though carefully sought for. WOODWARD, 

 M. F., 1'. Z. 8., 1N!>2, p. 184, Plate xm. 



*101. Lumbricus herculeus, Savigny (= L. ayricola, Hoffmeister), 

 having an asymmetrical arrangement of the generative organs, &c. 

 < >n the left side the arrangement was normal ; the ovary being in 

 the 13th segment, the oviducal opening in the 14th, and the open- 

 ing of the vas deferens in the loth segment (Fig. 24). 



< >n the ni//if side each of these structures was placed in the 

 segment anterior to that in which it is normally found: the right 

 ovary was in the 12th, the external opening of the right oviduct 

 was in the 13th, and the external opening of the right vas deferens 

 waa iii the I4th segment. The spermatheca- were normal on the 

 left side, being placed in the 9th and 10th segments, but on the 

 right side one spermat heca only was present, that of the 9th 

 se^mrnr. r |-],,. vesiciihe seminales were present as usual in the 

 !>th and llth segments, but there was no vesicula in the 12th 



In I'.i nun's enumeration tlie ordinal number of these segments is one less than 

 in that commonly used: the latter sv.-t. m i> mln^ti'd above. 



