ment of well-known species of niollusca from Port Jackson and 

 Botany ]3iy 



Tlie author rolatos the clisco\ery of lod ])lood in t\\() of the 

 specios Atrn trapezia and SoIpii loaim, \vlnchistlie inoie niteiest- 

 1114 i^ the siiMe exceptional peculiirity exists m 1 J^iitish species 

 of "^o/t It, md an American species oi Area Theie is also <in 

 riccoujit of the micioscopic examination of tlu l,i1] <ip])iiatus of 

 the rock ojster, Ostr pa mordax, from a\ hull it ipp* u^ tliat the 

 o\aof o\stersarenursedinthegill cli imlx iMiiitil th(\ ne h it( hed 

 a fact of <j;r tat importance in oystei cult i\ it ion Otlui m\\ facts 



One matter, howe\er, which occupies the s^reater poition of the 

 paper, it. the dibCO\ery of sense organs, especially e\es in the sliells 

 and opercula, as well as similar developments u\ tlie '-oft tis-,ues 



Th( ol.^PiMtionsof Di Semper and Pi (.ttw)i M(;m( \ on these 



Trvjonia amongst the bivalves 



But the most singular part of the in\ ( sti^' itions i^ tli it vs hu h 

 refers to the genus Ttiyonia The author finds th it eich ot the 



the eje of a fly, and each of the facets has a cornea, lens, retina, 

 and optic nerve. 



N'icwcd under the microscope, the outer surface shows ribs and 

 niiscd tulxTcles, on each portion of wliich there is a pavement of 

 biilliantly-refracting eyes as small and as close as those of an 

 insect. A section of the shell shows the nerves of these organs 

 uniting in wliat the author believes to be a large nervous centre 

 or brain. From this other large nerves are given oft", so that the 



