820 LARVAL CESTODE PARASITES OF FISBES— LINTON. vol.xix. 



lengtli of blastocyst, about 20; breadth of head of embryo, 0.72; diam- 

 eter of neck, 0.2; length of bulbs, 0.9; length of hooks, 0.06. The 

 anterior jtortiou of blastocyst was oval, with about three constrictions 

 posteriorly, giving it a somewhat chrysalis outline. The length of the 

 bead and neck of embryo in one instance, 4.5 mm.; in another, 5.2. 



Hill ' has examined some of the developmental stages of a Synboth 

 rium agreeing closely with published descriptions of S. JiUicolle, which 

 he finds in the peritoneum surrounding the intestine of the jewfish 

 {Sekcna aquila). 



The following conclusions are reached by that author: 



1. The so-called blastocyst or endocyst is the serial homologue of 

 the caudal vesicle of the Cysticerci. 



2. The wall of the invagination sac represents the body of these 

 forms. 



3. The scolex, consisting of head and neck, arises from the bottom of 

 the invagination sac, as a knob-shaped process, which, bj^ subsequent 

 elongation and differentiation, gives rise to the fully formed scolex. 



EXPLANATION OF PLATES. 



Many of the figures were drawn with the aid of an Abbe camera Incida, mounted 

 on a Zeiss stand No. VII. 



Where not expressly stated otherwise, it is to be understood that the sketches are 

 made from alcoholic specimens. 



Plate V, tigs. 8-11, were drawn by Mrs. M. B. Linton, other figures by the author. 



Plate I. 



Ligula cMlomycieri, from spleen of Chilomijcterus geometricus. 



1. Anterior end of specimen. Enlarged three times. 

 Larval dibothrinm ( ?) from cyst in Sarda aarda. 



2. Entire specimen. Enlarged eighteen times. 



3. Posterior end of same, cleared in oil of cloves, enlarged about fifty times. 



Larval Echeneihothria. ? 



4. Scolex of specimen from intestine of Limauda ferruginea. Enlarged two hun- 

 dred and twenty-five times. 



5. Specimen from intestine of Lopliins jnscniorius, showing pseudosegment, life. 

 Enlarged twelve times. 



6. Specimen with head retracted from gall bladder of Cynoscion regalis, life. 

 Enlarged sixty times. 



7. Specimen from same host, myzorhynchus riinuel-shaped, life. Enlarged sixty 

 times. 



8. Specimen from gall bladder of C. regalis, r red spots, life. Enlarged thirty-six 

 times. 



9. Scolex from same host, head retracted, life. 



10. Scolex from same host, myzorhynchus extended, life. 



11. Abnormal specimen from gall bladder of C. regalii, life. Enlarged twelve 

 times. 



12. Specimen from gall bladder of C. regaVis, compressed, life. Enlarged twenty- 

 four times. 



•Proceedings of the Linaeau Society of New South Wales, IX, p. 75. 



