44 ILLINOIS BIOLOGICAL MONOGRAPHS [332 



each main tract, the latter in the jointed portion of the strobila only, but in the 

 true scolex to form an irregular transverse commissure situated among the pro- 

 boscides. Excretory system composed of one large median and shghtly dorsal 

 vessel and two smaller lateral and ventral, all uniting in the secondary scolex 

 behind the nerve ring to form a vesicle. No genital cloaca; opening of vagina 

 close behind that of cirrus, towards the anterior end of the proglottis, that of 

 the uterus much farther back. Sphincter vaginae present. Vitelline glands 

 in numerous follicles arranged cylindricaUv around the testes, both continuous 

 from proglottis to proglottis, leaving clear areas opposite the central genital 

 ducts; large vitelline reservoir. Vas deferens provided with a sperm-reservoir 

 at its posterior end near the middle of the proglottis; whole of the course of the' 

 duct dorsal to the uterus-sac. Uterus-sac when gravid occupies the whole of 

 the middle of the proglottis. 



Type and only species: H. globuliforme Cooper. 



The genus is here emended owing to the elevarion to subfamily rank of a 

 num.ber of the characters given in m}' original generic description. 



HAPLOEOTHRIUM GLOBULIFORME Cooper 1914 

 [Figures 9, 10, 43, 44, 65-67] 

 1914 Haphbothrium gtobulijorme Cooper 1914:2, 1914a:l 15 



Specific diagnosis: With the characters of the genus. Small worms, pri- 

 mary strobila up to 70mm. in length, secondary to 110mm., with respective 

 maximum breadths of 0.3 and 0.6mm. Primary scolex 0.35mm. in diameter, 

 indefinite in length, bulbs 0.40 to 0.45 by 0.06 to 0.07mm.; secondary scolex, 

 0.4 to 0.5 by 0.25 to 0.4mm. Auricular appendages disappear at about the 25th 

 segment in normal secondary strobilas. Foremost secondary segments tet- 

 ragonal, middle and posterior much elongated and considerably depressed. 



Cuticula 3 to 4/x in thickness, subcuticula 25/x. Chief nerve strands IS^i in 

 diameter, narrowing intersegmentally. Terminal excretory vesicle 20 to 40^i 

 in diameter. 



Genital organs begin at about the 15th proglottis. Opening of cirrus and 

 vagina 0.02 to 0.07mm. apart. 



Testes spherical to elHpsoidal in shape, 70 to 115^ in maximum length; 

 about 80 in each segment. Vas deferens median, elongated, only shghtly 

 coiled, 10 to 55;Lt in diameter. Vesicula seminalis broadly spindle-shaped, 140 

 by 90/x. Cirrus 20 to 30/x in diameter; cirrus-sac, 0.16 to 0.21 by 0.14 to 0.16 

 by 0.18 to 0.20mm. 



Vagina 20 to 30^c in diameter at its opening, 56^t in its enlarged distal por- 

 tion. Receptaculum seminis 30 to 45^1 in diameter, spermiduct 5 to lO/j and 

 very muscular. Ovary hippocrepiform, the limbs directed posteriorly and 

 often fused with each other, the isthmus narrow. Ova from latter 10 to 12ju 

 in diameter, their nuclei, 7/x. Oocapt 15 to 25/i in diameter, oviduct 8 to 15/i. 



