STRUCTURE AND DEVET.OPMENT OF COEEOPLANA. 7 



winter months, when only a few specimens of it were secured during 

 a period of time in which more than a hundred specimens of the other 

 species were collected. In the year following, both the species were 

 strikingly rarer, and that to an extent that I searched on occasions 

 strenuously for them in vain for days in succession. 



The third species, C. bocki, is quite common on the Dendronephthya 

 sp., that thrives in tiie littoral of the neighbourhood of Misaki. It 

 occurs in adherance to any part of the surface of the stock of the 

 alcyonacean either to the stalk or to the crown (pi. i, fig. i), and may 

 be found in such abundance that I have secured as many as fifty or 

 sixty, and sometimes even more than a hundred, specimens from one 

 and the same stock of a moderate size. 



It is by no means difficult to keep the animals alive in a jar 

 provided the water is fairly pure. To detach them from the substratum 

 to which they adhere, it is necessary to use a pippet, otherwise the 

 specimens will always suffer damage. 



The three species (PI. i, figs. 2-4) may be readily distinguished 

 by their colours, though this is subject to a certain degree of variation 

 within each species. The colour variation is especially pronounced 

 in C. willeyi and C bocki. The former (fig. 2) may be of a deep 

 purple, a pale rosy or a reddish colour, or of a colour intermediate 

 between any of these. The peripheral margin of the body and the base 

 of " dorsal tentacles " are marked with scattered yellowish-white spots, a 

 feature which never obtains in the other two species. The latter (fig. 4) 

 shows a coloration which is about as much, or even somewhat more 

 widely variable. This species is characterized by exhibiting a rather 

 conspicuous marking on the ground colour. The marking consists of a 

 number of branching and anastomosing stripes, which on the whole run 

 along the tentacular axis and may be deep vermilion, dark red, brick- 

 red, pinkish, orange or greyish in different individuals. The stripes 

 number a dozen or more in large specimens; they may be discontinous 

 and irregularly streaky in small ones. In all cases the marking grows 

 indistinct towards the margin of the body. The ground colour of the 

 body is usually similar to that of the stripes, though very much lighter 

 in tone. Rarely it is of a colour which more or less contrasts with 

 that of the stripes, for instance, I have found some cases of individuals, 

 in which it was of an orange hue while the stripes were vermilion. The 

 stripes constitute a feature peculiar to the species; it is found in neither 

 of the remaining two species, both of which being rather uniformly 



