298 rUOCEKDINGS OF TIIK MALACOLOfilCAT, SOCIKTY. 



The muscular system is well developed, but I was imable to follow 

 this out iu detail. The columellar niusele is very strong, and has 

 a glistening appearance where it clasps the columella. The introvert 

 muscles have alread)- been mentioned, and I regret not being able to 

 give a definite account of the muscles actuating the radula. 



The radula has a formula 2:1:1:1:2, and is tinted a fine red 

 purple colour. The forms of the teeth are shown in Fig. 9, much 

 enlai'ged. The central tooth is multicuspid, the central cusp being 

 much the largest, and there appear to be about seven smaller cusps on 

 each side. The laterals are multicuspid, the first being much the 

 largest, and is directed inwards and downwards. The unciui are long, 

 curved, and simple. 



The forms of the radula teeth are not unlike those of Cassis sulcosa, 

 Born, as given by Cooke, but in that species neither the middle cusp 

 of the central tooth nor the first cusp of the laterals is so well 

 developed. In Cassis saburou, Adanson, according to Woodward, the 

 innermost of the uncini are cusped. 



^ot being familiar with the anatomy of forms allied to Cassidaria 

 rugosa, I am unable to go into tletails of comparison, but hope at some 

 future date to have the opportunity. 



In conclusion, 1 must thank ]\lr, E. A. Smith, Mr. E. R. Sykes, and 

 Mr. E,. H. Eurne for their kind assistance, and for the trouble they 

 have taken iu aiding me with suggestions and references. 



BOOKS CONSULTED. 



(1) Kiener : Monograph on Cassidaria. 



(2) Dr. N. Tiberi, " Sur les especes du genre Cassidaria qui vivent 



dans la Mediterranee " : Journ. de Conch., ser. iii, vol. iii, 

 pp. 150-155. 



(3) Dr. P. Fischer : "Manuel de Conchyliologie," etc., 1SS7. 



(4) Kemy Perrier : " Eecherches sur Tauatomie et I'histologie du rein 



des gasteropodes prosobranches," 1889. 



(5) r. Bernard : " Eecherches sur les organes palleaux des gastero- 



podes prosobranches," 1890. 



(6) H. Coupin: "Les Mollusques," 1892. 



(7) Eev. A. H. Cooke: "Molluscs" (Cambridge Natural History), 



1895. 



(8) A. Lang: "Textbook of Comparative Anatomy" (transl.), 1896. 



EXPLANATION OF PLATE XV. 



Fig. 1. — Animal with the mantle cut away along the right side and folded back. 

 The part carrying the rectum had "to be divided from the rest to enable the 

 folding back to be done without destroying various tissues. The penis has 

 been puslied a little to one side, and the seminal duct cut through and turned 

 away. The tioor of the branchial cavity is cut away, in ptut exposing the 

 salivary glands and a portion of the crop. 



Figs. 2-4. — In the text. 



Fig. 5. — A, plan showing buccal mass, salivary glands, and crop ; the inti-oveii laid 

 open. £, the posterior part of the crop laid open. C, transverse section of 

 crop. I), anterior part of crop and posterior part of the buccal mass laid open, 

 showing sacculation and entrance of sabvary ducts. 



