No. 638] 



MELIBE LEON IN A {GOULD) 



239 



dead. Later, this one also seemed dead, and it was 

 thought that the water had become stale. Melihe lay 

 absolutely motionless on the bottom, all its muscles com- 

 pletely relaxed, and showed signs of life only after the 

 water had been oxygenated for several minutes. It is 

 muscular relaxation of this sort that Melihe assumes 

 when it sinks from the surface to deeper water. After 

 this the writer became used to its death feigning and 

 needed only to oxygenate the water for it to become active 

 again, crawl along the bottom and side of the aquarium, 

 and after a while start swimming in the vessel. Changing 

 of the water could not be done indefinitely, as on another 

 morning a nidosome was found to have been deposited 

 by the animal during the night. It was a funnel-shaped, 

 transparent, gelatinous body adhering by the tapering 

 end to the side of the jar. Viguier, 1898, when trying to 

 prepare a specimen of Tethys fimhymia for fixation, ob- 

 served the same phenomenon. He, howevei'. did not 

 change or oxygenate the water: lie left tlic niiinial in it 

 for about two weeks, when he fountl tliat an cu-.u-body had 

 been deposited, the eggs having eeasetl to ilividc in the 

 four-cell stage. The nidosome of T. fiuthiuita is (luite 

 different in shape from that of M. Icouhta. In the case 

 of Melihe the eggs continued to divide until tlu^y were 

 transformed into larval forms, which actually tni-ncd the 

 whole nidosome into a \ il)ratinu' mass, 'riic (i<'V('lopnu'nt 

 continued, ai)i)ai\ ntly normally, until tlir lar\a' left the 

 capsules, when tlu'\' soon dit'd. That the di'lieate niol- 

 luskan youn.u- should die when coininu- in direct contact 

 with the watiT of the a.|uariuni was exptrti'd, as the 

 renewing of \\w water was stopprd after the nidosome 

 was deposited, it bein- thou.uht undesirable to disturb it 

 too much: after the deposition of the eoo-ma^s the water 



day to diy, so that the animal should not dir. When the 

 voun- Mrltlx's were hatehed the mother animal, without 

 beinu- further inseminated, laid another nidosouu", which 

 also hatched two weeks later. 1Mie eggs of the lirst nido- 



