4 Bibliography. 



of parasitic castration, the discovery of which is due to him. Reference to his valuable papers 

 and to others on this subject are given in the special Bibliography at the end of Chapter 5, 

 and in that Chapter my researches founded on his work are described. 



Delage (17) replied to Giard's criticism, and in answer to the latter's accusation of 

 entertaining preconceived ideas as to the fixation of the larvae, remarks, "J'ai fait fixer des 

 milliers de Cypris. Toutes se sont attachees aux pattes, au thorax, etc. aucune a la face ven- 

 trale de l'abdomen; d'ou je conclus que la fixation n'a pas lieu sous l'abdomen. M. Giard n'a 

 jamais vu la fixation, pas plus a l'abdomen qu'ailleurs, et il conclut que c'est a l'abdomen que 

 se fixent les Cypris. Lequel de nous juge d'apres des idees preconcues?" 



In 1888 Hoek (19) published an account of a new species of Sylon, and the following 

 year Giard (20) in commenting on this species uses the fact that the basilar membrane is 

 separated from the intestinal wall by a thick muscular mass as an argument against the inde- 

 finitely localized fixation advocated by Delage for Sacculina. He further states that Sacculina 

 "garde constamment, comme je l'ai indique, ses rapports avec l'exterieur", and this we take to 

 be a denial of the occurrence of Sacculina interna. 



In 1S91 Giard (21) comments upon certain Ascothoracica, and introduces a discussion 

 upon the genus Sphaerothylacus which lives in colonies fixed to the branchial chamber of 

 Ascidians. Giard holds that Sphaerothylacus is a link between Ascothoracida and Rhizocephala, 

 and concludes — "la seule connaissance de ce type interessant suffit a demolir le roman 

 echafaude par Delage avec une mise en scene qui a pu en s'imposer a beaucoup de zoolo- 

 gistes. Nous aurons occasion de revenir prochainement sur cette gigantesque mystification". 



In 1898 Schimkewitsch (22) gives an account of the discovery by Pekarsky of an endo- 

 parasite stage in the life-history of Peltogaster corresponding to Delage's Sacculina interna. 



In 1 900 Delage (23) states that he found a young crab at Roscoff with a Kentrogon 

 larva attached to a hair on one of its legs, and when the crab moulted he preserved the inte- 

 gument with the remains of the Kentrogon on it. Some months later, a Sacculina interna 

 appeared upon the crab's intestine. 



In 1901 Duboscq (24) investigated the spermatogenesis of Sacculina carcini and remarks 

 in a footnote: "Le stade de Sacculina interne n'est pas niable. Des coupes seriees montrent 

 qu'il n'y a, d'abord aucun rapport, meme de contiguite entre la jeune Sacculine et Perithelium 

 externe du crabe". 



In 1902 Coutiere (25) published a series of notes on a most interesting gregarious 

 parasite of the Alpheidae for which he has created the generic name Thylacoplethus. The 

 author considers that since the roots of the parasites are confined to a limited area round the 

 intestine, this parasite does not pass through an internal stage similar to that described by 

 Delage: for Sacculina carcini. 



I have now summarised the chief papers which bear upon the controversy as to the 

 fixation and endoparasitism of the Rhizocephala. The position which Giard originally took 

 up on the appearance of Delage's work and from which he has never withdrawn, has naturally 



