179 



the formation of the sheath commences round the valves in a depressed 

 wavy manner, as in the preceding species, and Dr. Gray places it for this 

 reason in his genus Warnea. T do not regard this wavy depression as 

 having existed whilst the mollusk was in the bivalve stage of its existence, 

 and would refer A. Cumingianum to another section. 3. A. Javanum, 

 pulc/mtm, and radix (Aspergillum, Penicillus, and Clepsidra, Gray), in 

 which the sheath is attenuated, and is closed in at the bottom by an ela- 

 borately perforated disk, with a more or less densely branched, finely tubed 

 frill. 4. A. tuberculatum and clavatum (A/jtene, Gray), in which the 

 sheath is slender, agglutinating sand and fine pebbles, and is closed at the 

 bottom by a disk of small size, only lightly promiscuously perforated, en- 

 circled by a regular well-developed frill of a characteristic sloping growth ; 

 the valves of this type have the shelly wall of the sheath projected over 

 them in a peculiar biforked manner. 5. A. agglufiuans and Philipphiense 

 (Foegia, Gray), in which the tube is club-shaped, densely agglutinated 

 with sand, pebbles, and shell-debris, and is contracted below the disk, 

 taking the form of a small clump of short, wider tubes. 6. A. Straugei 

 {Ilumphreyia, Gray), the adherent species already described, of which Dr. 

 Gray constitutes a separate subfamily. 



All the Aspergilla belong to the Eastern Hemisphere. A. vaginiferum 

 inhabits the Red Sea, A. Javanum and its allies inhabit the eastern seas, 

 about the Philippine Islands, Java, Ceylon, and Singapore, and the more 

 distorted forms are from Australia and New Zealand. 



1. agglutinans, Lam. 



2. annulosuin, Desk. 



3. clavatum, id. 



4. Cuuiingianum, Chenu. 



5. Delessertianum, id. 



6. dichotoraum, id. 



7. disjunctum, Des/i. 



/Species. 



8. incertum, Chenu. 



9. incrassatum, id. 



10. Javanum, Lam. 



11. Novse-Zelandise, id. 



12. Philipphiense, Chenu. 



13. pulchrum, Desk. 



14. radix, Desk. 



15. semifimbriatum, Ch. 



16. Strangei, Adams. 



17. tuberculatum, Chenu. 



18. vaginiferum, Lam. 



19. Zebuense, Chenu. 



Figure. 



Aspergillum vaginiferum. PI. 46. Pig. 247. Shell, originally a small 

 bivalve, imbedded in the wall of a sheath, which is thrown up through 

 the sand, particles becoming agglutinated to its surface, the extremity 

 emerging from the sand, bearing three frilled edges, each of which 

 has formed the termination of the sheath at different periods. The 

 lower end of the sheath below the imbedded bivalve is covered in 



