79 
external lamellated cuticle and an inner parenchymatic layer surround- 
ing a lumen containing a fluid. This is the stage described as the Aceph- 
alocystis , a the name being based upon the absence or the supposed 
absence of heads. As a matter of fact, the so-called acephalocysts 
probably contained heads in not a few cases, but as these scolices are 
small they might have been overlooked. Not all so-called acephalo- 
cysts are true echinococci. 
Fig. 128. — Sexual organs of adult tapeworm, Echinococcus granulosus: cir. p., cirrus pouch; ov., ovary; 
ov. d., oviduct; as., receptaculum seminis; va., vagina; v.d., vas deferens; v.g., vitellogene gland. 
Enlarged. (After Leuckart, 1886, 747, fig. 318.) 
The brood-capsules may form directly on the parenchymatic layer, 
thus giving a granular appearance to the parasite, and this is evi- 
dentty the explanation of the use of the name granulosus by several 
authors. 
* 
In other cases daughter c}^sts form and are found floating in the 
fluid of the mother cysts; granddaughter cysts may form in the daugh- 
ter cyst; brood capsules may form in the mother c} T st, the daughter 
cysts, and the granddaughter cysts. This variation with endogenous 
/ 
a Names based on the acephalocyst: Acephalocystis Lsennec, 1804; .4. humana Lue- 
dersen, 1808; A. suilla Luedersen, 1808; A. ovoidea Lsennec, 1812; A. cystifera Lsen- 
nec, 1812; A. ansa Laennec, 1812; A. intersecta Lfennec, 1812; A. surculigera Lfennec, 
1812; A. granosa Lpennec, 1812; [.4. plana Lsennec, 1812 = Ovuligera carpi Dupuytren, 
is not an echinococcus]; Acephalocystus communis Herat, 1821; Acephalocystis com- 
munis Lfennec, 1825; A. eremita Cruveilhier, 1829a; A. sterilis Cruveilhier, 1829a; 
A. socialis Cruveilhier, 1829a; A. prolifera Cruveilhier, 1829a; Acephalocistis socialis 
Cruveilhier, 1829a; A. prolifera Cruveilhier, 1829a; Acephalocystis endogena Kuhn, 
1830 and 1832 {A. socialis vel prolifera renamed) ; A. exogena Kuhn, 1830 and 1832 
(A. eremita vel sterilis renamed); A. granulosa delle Chiaje, 1833 (for A. granosa 
Lsennec); A. prolifera socialis Cruveilhier of delle Chiaje, 1833a; ^4. eremita sterilis 
Cruveilhier of delle Chiaje, 1833a; A. simplex Goodsir, 1844d; “A. macaci ?” Cob- 
bold, 1861e; ? A. ovis traoelaphi Cobbold, 1861e. 
