90 ' Mr Dalyell on the Propagation of Scottish Zoophytes. 



cipient tentacula were indicated in one, and in nineteen days 

 eight or nine could be enumerated in another, which, now ma- 

 tured from its ciliated animalcular form, had affixed itself as 

 a young actinia by the base. Others also adhered, and were 

 actjuiring a cylindrical shap«, but their tentacula were of later 

 evolution. 



Thus, at an early stage, the actinia appears under a peculiar 

 form, altogether different from its perfect shape ; it is endowed 

 with vigorous action, and provided with certain external organs, 

 which are obliterated as it becomes stationary, and as others are 

 unfolded. 



II. Having passed per saltum to the Alcyoniiim^ we find it 

 consist of a compact gelatinous or fleshy matter, studded with in- 

 numerable cells sunk in its substance, which are inhabited by 

 vivacious hydrae. Diff^erent species or varieties occur in the 

 Scottish Seas, especially the gelatinosum, and a thin, green, flat- 

 tened palmate kind, which has perhaps escaped the notice of na- 

 turalists hitherto. 



A white, opaque, ovoidal, or nearly circular, flattened cor- 

 pusculum, previously invisible, issues from the fleshy part of 

 these products, whence it seems to be elicited, particularly by 

 the influence of the light. On removal of a small specimen, that 

 had already afforded many, from a dark situation to a moderate 

 degree of light, at least 150 quitted their recesses within an 

 hour. These beings are endowed with much greater activity 

 than the corpuscula of the actinia ; their courses are alike di- 

 versified : they swim through the water in all directions, regu- 

 larly and irregularly ; ascending to the surface, or descending to 

 the bottom : pursuing a straight line, describing an orbit, or 

 tumbling about among the neighbouring substances. Meanwhile, 

 as if of soft consistence, their form alters, and the action of the 

 cilia environing the body, is alternately accelerated and relaxed. 

 At length, having become stationary, a margin diffuses around 

 the body, and supervening transparence of the centre soon ex- 

 poses an immature hydra within, which in nine or eleven days 

 is displayed perfect from its cell. The inner surface of each 

 tentaculum is now clothed by a double row of stout dark cilia in 

 rapid motion, but in opposite directions, for as those of one side 



