4o8 



NAOKATSU VANAGI AND YAIC1URÜ OKADA : 



2. Scutum not divided • M. occidentalis. 



2. Scutum divided .1/. occidentalis, var. catalinensis.' 



3- Scutum present M. longispinosa. 



3. Scutum not present 4. 



4. Zoœcium with a single spine M. symfodia. 



4. Zoœcium with two or more spines M. symfodia, var. sagamiettsis. 



I Menipea 1otiffispinos€t. n. sp. 



Pl. VI., fig. 3 ; textfig. I. 



Zoarium forming a white delicate tuft, 27 mm. in height, dichoto- 

 mously branching. Internodes consisting of a variable number (4-10) 

 of zoœcia, with distinct joints of a faintly yellowish colour. Zoœcia 

 biserial, alternate, rather loosely connected laterally, attenuated below, 

 convex in front ; their aperture elliptical, about one-third as long as 



zoœcium, with slight- 

 ly thickened marginal 

 wall. Zoœcium pro- 

 vided with very long 

 and delicate curved 

 spines segmented at 

 base : three of them 

 occur close together 

 on the upper outer 

 angle of the aperture, 

 projecting sideways ; a 

 fourth, situated lateral 

 to the lower end of 

 aperture, is obliquely 

 distally directed ; a 

 fifth, similarly directed 

 may arise from a some- 

 what lateral point on 



Fig. I. Meni pea /ungi spinosa, n. sp. 



A. Portion of a branch enlarged, showing oœcium and 

 apertural spines. Frontal view, x 32. 



B. Dorsal view of zoœcia, showing root-chambers and 

 the position of dorsal spines. x57- 



