Noncalcarea 139 



Other halichondrine sponges (Lissodendoryx, Microciona) breed dur- 

 ing the summer (July- August) at Beaufort, N. C; Stylotella during 

 October in the same locality. Larvae may be reared in the same way 

 or may be placed in wire gauze cages after attachment and hung in a 

 live box. 



In sponges in general, fertilization is internal and the egg develops in 

 the body of the parent to the stage of the ciliated larva. Sponge eggs 

 and embryos are commonly abundant in a breeding sponge and may be 

 seen scattered through the interior with the naked eye. In some marine 

 sponges asexual masses analogous to spongillid gemmules develop likewise 

 in the body of the parent into ciliated larvae. In order to obtain larvae 

 all that is necessary is to place a breeding sponge in an aquarium jar. 

 (See Wilson, 1894.) 



GROWTH OF SPONGES FROM FUSION LARVAE 



The ciliated larvae of Lissodendoryx carolinensis may easily be made 

 to fuse with one another after they have begun to creep over the bottom 

 of the culture dish and are thus approaching the phase in which they 

 attach. It is only necessary to bring them in contact, coaxing them 

 together with needle and pipette in a deep, round watch glass. The 

 compound larva so produced has a feeble locomotory power. Using 

 pairs that are nearly motionless, fusion masses of desired shapes may be 

 produced on cover glasses. Or small excavations may be made in 

 paraffin-coated dishes, and the larvae driven into such holes in large 

 numbers. In this way, cake-like masses may be produced measuring 3-4 

 mm. in diameter. The smaller compound masses metamorphose without 

 difficulty. The larger in the actual experiments died, sometimes after a 

 partial metamorphosis. (See Wilson, 1907.) 



Bibliography 



Wilson, H. V. 1894. Observations on the egg and gemmule development of marine 



sponges. /. Morph. 9:277. 

 1907. On some phenomena of coalescence and regeneration in sponges. 



J. Exper. Zool. 5:245. 

 1907a. A new method by which sponges may be artificially reared. Science 



25:912. 



191 1. Development of sponges from dissociated tissue cells. Bull. U. S. Bur, 



Fish. 30:1. 



