8 Lazelle B. Sturdcvant 



3,000 fx, or ten times as broad as long. At 60 cm. from the scolex 

 they are 450 /x by 2,820 /a, or six times as broad as long. At 80 

 cm. from the scolex 900 /x, by 2,910 /x, or three times as broad as 

 long. At the end of the strobila they are 660 /a by 2,760 /x, or four 

 times wider than long. This shows that disproportionate con- 

 traction has occurred throughout the strobila. 



Figure 9 shows a few proglottides from this specimen at 20 cm. 

 from the scolex. To what extreme the longitudinal contraction 

 may be carried in the process of fixing is shown in figure 5 from 

 another one of my specimens, where, at one-fifth of the total 

 length of the strobila from the head, the proglottides measure 

 100 iJL by 2,280 ju, or nearly twenty-three times as broad as long. 

 These measurements are taken midway between anterior and pos- 

 terior borders. The serration throughout the strobila is not so 

 striking, since the posterior border of each proglottid only 

 slightly exceeds in length the anterior border of the proglottid 

 following. The lateral margin of each proglottid usually shows 

 a slightly convex outline, while the postero-lateral angle is rather 

 blunt. Ripe proglottides are usually given oiT from the end of 

 the worm in groups of from two or three up to fifteen in each. 

 The decrease in width and the concavo-convex outline of the 

 proglottides increasing toward either end of the group are rather 

 characteristic. One group coming from my longest specimen 

 contains fifteen proglottides. 



The genital pores are regularly unilateral and on the left side 

 at the junction of the anterior and middle thirds of the proglottid. 

 Occasionally a proglottid may be found where the genital pore is 

 on the right side. My specimen is not new in that regard, I have 

 not observed calcareous bodies in my specimen, since there was a 

 trace of acetic acid in the fixing fluid and the worm was destained 

 in acid (HCl) alcohol. Ransom describes them as oval, measur- 

 ing 8 to 13 by 4 to 6 IX. They are usually rare in this species. ' 

 The nervous system in this species has been described by 

 Zschokke. Throughout the strobila may be found two large 

 longitudinal nerves, one near either border of the worjn. Just 

 above and below each of these (dorsad and' ventrad) may be 

 found an accessory longitudinal nerve ; hence two on either side,. 



142 



