372 



36 



ferenl, that we lind the types of alga rouiul which the remaining forms group 

 themselves in a natural way. 



If we now first consider the specimens we meet with in the more exposed 

 localities behind the corah-eefs, it will appear that these are characterized by being 

 relatively small, but on the other hand rather strongly developed. The erect shoots 

 are often only 5 — 6 cm. high, but richly ramified with densely-crowded branches, 

 which bear about 3 — 6 (sometimes still more) rows of ramuli. These are present 

 not only on the branches themselves but also often on the main shoot quite down 

 to the rhizome. It is especially forms of the var. mamillosa (Fig. 13) we have here 

 and which are characterized by the short obovate, densely-placed ramuli which 

 cover the erect shoots often down to the rhizome (see Fig. 13, cfr. also Weber, 34, 



PI. XXVIII, fig. 3 

 5 and 6). 



When the 

 ramuli are a little 

 longer and more 

 widely placed, 

 being commonly 

 3 or 4 rows, we 

 get forms of the 

 var. tgpica (Fig. 

 14) , which also 

 occur in these 

 localities , per- 

 haps however in 

 places a little 

 more sheltered or 

 in deeper water. 

 Even small dif- 

 ferences in the local conditions of life seem often to give a corresponding difference 

 in the specimens occurring. On the shores of the pilot isle, Protestant Cay as it is 

 called, at Christianssted, I have thus found in shallow water near the surface of the 

 sea, where it was somewhat exposed, a low compact form with 4—5 rows] of ramuli, 

 which in my opinion must be considered as an intermediate form between var. 

 mamillosa and var. typica; but further from the shore where the bottom fell steeply, 

 the var. typica was growing in about 6— 8 feet of water with only about 3 rows 

 of somewhat longer ramuli. Fig. 14 shows one of the forms of var. typica we 

 meet here; compare also Mme. Weber van Bosse, Monographie, pi. XXVII. fig. 1 

 and especially |)1. XXVIII, fig. 1. 



I have not found any specimens which I believe might be referred to the typical 

 var. ericifolia (cfr. Weber van Bosse, Monographie, p. 335, pi. XXVIII, fig. 8) and I 

 cannot therefore from personal observation say where this form has its real habitat; 



Fig. 15. CauUrpa cupressoides (Vahl) Ag.' var. lijpica Weber van Bosse. 

 In shallow water. The lagoon of Christianssted. (About 1 : 4.) 



