SPURILLA BRAZILIANA MAC FARLAND 95 



and last plate 54:1 151. In this radula the basal diameter of the 

 plates varied from 00.09 mm. in the first, to 0.55 mm. in the 

 twenty-sixth. In Sp, neapolitana the three central denticles are 

 very small or rudimentary, while in the Brazil species the central 

 denticle is valid and much larger (PL XVI, fig. 89). 



Salivary glands. The extremely long salivary glands are 

 shown in figs. 86 and 87 of PI. XVI. They have the same general 

 appearance and relations as exhibited in the other species of 

 Spurilla. 



Central nervous system. The ganglia of the central nervous 

 system are inclosed in a strong closely applied connective tissue 

 capsule, from which in the specimen at hand the ganglia had 

 in part shrunken away, the general preservation precluding any 

 satisfactory detailed study of the cells and fibre tracts in sections, 

 though the general relations could be readily made out. For 

 comparison several specimens of Sp. neapolitana were also dis- 

 sected. In general there is no great difference between the two 

 species, but some marked discrepancies were noted between the 

 Neapolitan species and the figures given for it by Bergh ('77), 

 and by Trinchese ('78), especially in respect to the origins of 

 the nerves. In Bergh's fig. 4, PI. XII, the nerves appear to be 

 represented in a diagrammatic fashion, they being neither num- 

 bered, nor mentioned in the text, the author manifestly laying 

 most stress upon the form and grouping of the ganglia. In the 

 earlier paper of Trinchese, "Nuovo Ricerche sull' Organizzazione 

 del Cervello degli Eolididei," Memorie deH'Accademia delle 

 Scienze dell'Instituto di Bologna, 1875, Serie III, T. V, he devotes 

 his attention to certain peculiarities of the nerve cells as seen in 

 preparations, cleared in glycerine and flattened under a cover 

 glass, his figure of Tavola I giving but a faint idea of the actual 

 form of the ganglia and the origins of their nerves. In his 

 "Anatomia e Fisiologia della Spurilla neapolitana," cited above, 

 this is corrected in the figures of Tavola XI, which present the 

 best representations of the central nervous system of this Eolid 

 yet published. In the figure of the same for Sp. braziliana, given 

 on PI. XIX, fig. 96, I have adopted the designations used by 

 Trinchese for the nerves for the sake of ease of comparison, 

 though I must disagree with him as to the actual origin and 



