1 70 MERISTIC VARIATION. [PART I. 



(instead of about 20 mm.), and one with five pores measured 

 28 nini. (instead of 50 nun.). L., )>. 571. 



12G. Ta-nla. Case quoted by Leuckart from HELLER of a Tania having generati\. 

 "I'l-iiinrs I'lar. <l on the turfaet of the segments. Leuckart himself has never seen 

 an i x:mii'li- of tliis variation. [Original reference not found] L., p. 570, Note. 



1-J7. Taenia solium and T. saginata. Specimens are known 

 having two generative pores opposite each other at the same level. 

 In .such cases each leads to a male and a female duct with cirru 

 sac and receptaeulum seminis; but the organs for preparing the 

 ova are normal in construction, as the two vaginae lead to a 

 common uterus and shell-gland. Two cases only have been seen 

 by LKTCKART and he cites another from WERNER. L., pp. 52!) 

 and ~>7 1 . 



Taenia solium in which the pores are normally alternating, 

 may be found with symmetrically developed pores; and on tin 

 contrary, T. elliptica in which they are normally symmetrical, 

 may occur with an- asymmetrical arrangement. L., pp. 353 and 

 529. 



l-2'.i T. saginata: in a chain of about 6'5 metres in length, and 

 containing some (>50 joints, there was found a single, heart - 

 shajH-d, supernumerary joint like those described; a single joint 

 u.i- i.>mid with two genital pores, one being on each lateral border 

 at about tin- same level. 



The largest number of consecutive joints having the genital 

 jion-s on tin- same side was six. TUCKERMAX, F., Zool. Anz., XL, 

 L888, ].. !4. 



|:;o Taenia coenurus. Speeimen observed by Leuckart in which 

 the l ;i >t s or Hi segments shewed a transposition of the generative 

 organs, those whieli usually lie at the distal end being placed 

 at the proximal. This change of position was especially seen in 

 the ease of organs engaged in the preparation of the ova. The 

 proximal proglot I ides of this individual were normal. The trans- 

 ition segment, between these two regions contained two simple 

 \eMcul.-e seiuinales and two marginal papilla? which were on 

 oppu-ite sides; bm in spite of the resemblance of these structures 

 to genital pores. neither opening, nor cirrus, nor vasa deferentia 

 could be distinguished. L., p. 504. 



I'll Amongst chains of normal proglottides it is not rare to find 



a segment containing male organs only. L., p. 504. 



Speaking generally, slight abnormalities are far more common 

 than great onea Nearly every specimen of Tapeworm has in- 

 di\idual peculiarities, and these generally repeat themselves in 

 the same chain of proglottides. This repetition of the same 

 abnormality in different parts of the chain is also the rule for 

 the great,. ] abnormalities also. L.. pp. .">:!!). 572 and 573. 



