M 0 LLUSCOl D A . 
317 
ant l in the Equatorial seas. They are inhabitants of the open sea, 
ail( l live immerged at considerable depths ; but when the nights are 
c alm they show themselves on the surface. As they spread thom- 
Se Wes abroad with a strong phosphorescent light, they resemble long 
ri hbons of fire, unrolling their long waving lines in spite of the waves, 
as in Pig. 127. What wonders they see who go down into the great 
^ e P ! What sights are reserved for the navigator who traverses the 
r °pical seas during the silence of night ! 
'When a chain of Salpas is drawn from the water, the rings separate, 
Fig. 127. Phosphorescent chain of Salpas on the surface of the sea. 
i. 4 ^ ihey can no longer be made to adhere. The social bond has been 
di, 
8 ®olved by superior order. 
Sal 
pas are sometimes met. with, isolated and solitary, whose exterior 
formation differs much from that which is proper to the connected 
l P a ; so different, indeed, that 
1 
jj l I’ a ! so different, indeed, that it might belong to another typo. 
v' 1 *' the observations of Ohamisso, of Krohn, and of Milne Edwards, 
a ' 6 re vealed some very remarkable facts. By dint of time, patience, 
Sa gacity, these observers have ascertained that the Biphora is 
a nd 
v ivi 
^ 'parous, and that each species is propagated by alternate generation, 
e young creature being unlike its immediate parent. One of these 
Nations is represented by the solitary individuals, the other by an 
