6 PROCEEDINGS OP THE NATIONAL MUSEUM vol. 81 



reticulate in plan. It will be observed that this order, by definition, 

 api^roaches close to some members, at least, of both the two preced- 

 ing orders. The fresh-water sponges might be placed here or in the 

 preceding group as a unit. Topsent does not discuss them in his 

 1928 article proposing the classification here considered. 



9. Dictyoceratina: Sponges with no proper spicules (some from 

 other sponges may become included as the sponge grows) but with 

 a decided reticulation of spongin fibers. 



10. Dendroceratina: Sponges with no proper spicules (see note 

 above) but with spongin fibers that branch and do not reunite, resem- 

 bling little trees in form. 



Topsent regards the first of these orders as also a class, the second 

 order as a second class, and the rest as a third class. 



SYSTEMATIC DISCUSSION 



Order CALCAREA Gray 



Family LEUCOSOLENIIDAE Minchin 

 Genus LEUCOSOLENIA Bowerbank 



LEUCOSOLENIA CONVAL7ARIA (Haeckel) 



AsciUa convallaria Haex^kex, 1872, vol. 2, p. 45. 

 Leucosolenia convallaria Dendy and Row, 1913, p. 725. 



Holotype. — Location unknown. 



Type locality. — Described from the Pacific coast of North Amer- 

 ica (California, Brown). The species has not since been found in 

 the State. 



Description. — Hollow cylinders 0.05-0.1 mm thick, 2-4 mm long. 

 Fragile, white, surface minutely hispid. The wall of the tube is 

 of simple ascon type, strengthened by usually two layers of quadri- 

 radiates only, of which the apical ray is from two-thirds to as long 

 as each of the facial rays. 



Remarks. — Ascon type sponges with only quadriradiates are very 

 rare. Hozawa (1929, p. 285) described a very similar one, Leucosol- 

 enia Jx-agoshimensis, from Kagoshima Bay, Japan, and Haeckel (1872, 

 vol. 2, p. 47) described another, Leucosolenia (AsciUa) japonica, also 

 from Japan. 



LEUCOSOLENIA MACLEAYI Lcndenfeld 



LcvGOsolenia macleayi IjEndekyeld, 1885, p. 1086. 

 Leucosolenia stipitata Dendy, 1891, p. 51. 



Holotype. — Location unknown. 



Type locality. — First described from Australia. 



