LEUCETTA. 



rarer large ones of a similar shape measuring 0-8 x 0-085 millim. ; very rare 

 spicules of an intermediate size are also met with. 



I have seen many specimens of Haeckel's Lencetta jirimigenia. They are all 

 slightly ramified ; 3-6 cylindrical pieces, with uneven surface, grown together 

 and meeting at sharp angles. These cylinders taper towards the terminal 

 oscula, and attain a length of 25 and a diameter of 8 millim. The gastral 

 cavity is large, the body- wall not exceeding 2 millim. in thickness. The 

 inhalant pores are covered with thin perforated membranes, and lead into wide 

 bulbous cavities, from the proximal ends of which the inhalant canals take 

 their origin. A great number of canals radiate from each subdermal lacuna ; 

 the latter have a diameter of 0*12 millim. The small spicules are very regularly 

 tangentially disposed in the surface in such a manner that they form a network 

 with hexagonal meshes, in which the pores are situated ; but there is not a 

 pore to each mesh. The spiculation of all these specimens is the same 

 (as above), corresponding to that of Haeckel's var. mkrorrhaplds of Leucetta 

 primvjenia. Eidley (7. c.) has obtained the same sponge from Torres Straits. 

 The similarity in the structure of my specimens and their constant difference 

 from other forms of Haeckel's species lead me to assume that this variety of 

 Haeckel's should be considered a distinct species. 



Geogkaphical Disthibution. — Australia? {Haeclcel). North coast of 

 Australia : Torres Straits Q Alert ') , South coast of Australia : Port Phillip 

 {Lendenfeld). East coast of Australia: Port Jackson {Lendenfeld). 



Leucetta megarrhaphis, Haeckel. 



Leucetta megarrliapliis (^Leucetta primigenia, var. megarrliaplus), E. Haeckel, Die 

 Kalkschwiimme ; eine Monographic, Band ii. Seite 119 (1872). 



The specimens of this sponge which I have seen are ii-regularly lobose, com- 

 pressed, and measure (the largest) 150 x 100 x 25 millim. The surface is 

 smooth. A few large oscula of an irregular shape are found near the margin of 

 the flattened sponge. The spirit-specimens are not well preserved ; they are of 

 a dirty brown colour. The inner part of the sponge is taken up by an extensive 

 gastral cavity of irregular shape, which, however, copies the outline of the 

 outer surface roughly, so that the body- wall is of pretty uniform thickness 

 throughout. In some places the opposite walls coalesce, and the sponge 

 appears solid. There seem to be only very small subdermal cavities, from 

 which, however, pretty large inhalants extend downwards; these are of 

 irregular, cylindrical shape ; some of them extend centripetally nearly to the 

 gastral wall ; at the end they bend round abruptly and form tangential 

 branch-canals, from which the small final ramifications are given off. These 



