REPORT ON THE ALCYOXARIA. 39 



4. Primnoisis amhigua, u. sp. (PI. IX. fig. 9). 



The colony is upright, bushy, expanded above, the branches spreading out prevalently 

 in one plane. 



The main stem is upright, bent towards several sides in its course. From its base 

 upwards it gives ofl' branches at acute angles, some of which have the stoutness of the 

 main stem and others are weaker. During their much twisted upward course the 

 branches ramify more and more abundantly, and send their fine terminal branches right 

 to the top of the colony. 



The twiors, which arise from the branches at moderate intervals from one another, are 

 long and slender and give off fine lateral twigs, which but rarely again bear twigs of the 

 fourth order. The branches arise from the stem and the twigs from the branches, 

 mainly on four sides, but two Ijranches, arising opposite to one another, are always more 

 strongly developed and ramify more in one plane, so that the colony acquires a some- 

 what bilateral appearance. The terminal twigs arise from one or two sides. 



The height of the colony reaches 140 mm. The thickness of the main stem near the 

 base is 3 mm. The length of the fine terminal branches is up to 11 mm., mostly 10 mm. 



The ccenenchyma is only preserved in the terminal twigs and some of the larger 

 branches. On the latter it is thin and transparent, on the thin twigs thick, and thickly 

 covered with polyps, which stand around the twig in spirals, each composed of four 

 polyps. 



Towards the base of the twigs the polyps are more scattered and on the thick 

 branches only sparsely strewn, at wide intervals from one another. Their form is club- 

 shaped. On the twigs they are directed obliquely upwards. Their length reaches 

 0'8 to 1 mm. 



The axis exhibits proportionally short, calcareous joints, which are cylindrical and 

 longitudinally fluted. The jointing can be followed even into the finest branches, the 

 points of which are always formed of a short, calcareous joint. In the stem the calcareous 

 joints have a length of 2 '5 to 4 mm.; the horny joints of 0"5 to 1 mm. The branches 

 arise from the calcareous joints, but not so regularly as in the foregoing species. j\Iauy 

 calcareous joints in the stem and branches give off no twigs. Very often only one 

 branch arises from a joint, then two, seldom three. The branches and twigs commence 

 usually with a horny joint. If the branch arises near the upper end of the calcareous 

 joint, then the horny base of the branch comes into contact with the horny joint of the 

 stem, hence many branches and twigs thus apparentl}' arise from the horny joints of 

 the stem. 



In the twigs the calcareous joints are longer than in the stem or in the thicker 

 branches, and measure from 4 to 5 mm. 



The spicules of the ccenenchyma are less dificrentiated from those of the 



