96 ART. 12, K. YENDO. 



Sargassuni énerve Ag. 



Plate XIII. Fig. 1-6. 



Spec. p. 17. — Id.: System, p. 279. — J. Ag.: Spec. Alg. I. p. 294 (exel. 

 sijn.). — Id.: Spec. Sarg. Austr. p. 61. — Id.: Anal. Alg. III. p. 55. — Kütz.: 

 Tab. Phyc. XI. Tab. 13.— Haeiot: Alg. de Yokosk. p. 218.— Mar- 

 tens: Preus. Exped. Tange, p. 116.— De Toni: Syll. Alg. III. p. 25. 

 — Id.: Phyc. Jap. Nov. p. 45. — Okam.: Enumer. Alg. of Jap. p. 149. 

 = Sargassum fulvellum Okam.: Enumer. of Alg. of Jap. p. 149. 

 = Spongocarpiis enervis Kütz.: Ueber d. Eigent. (Bot. Zeitg. 1843.) s. 

 55.— Id.: Tab. Phyc. X. Taf. 89. II.— Zd: Phyc. Gen. p. 

 365.— O'Kuntze: Ptevisio von Sarg. p. 220. 



Description of the species. The root is a depressed cone 

 with a simple erect stem on its top. In a shoot just starting 

 the leaves are sent off spirally upwards from very near the base. 

 The leaves are strongly retrofractive, linear-spathulate or cuneate, 

 irregularly dentated, attenuated below into a more or less elong- 

 ated petiole. From the petiole a costal elevation passes into the 

 lamina but disappears within a very short distance. The substance 

 of the leaves is thick but soft, dark brown in colour, and without 

 cryptostoma. Short lateral branches, not exceeding an inch in 

 length, with several large vesicles at each base, are seen on the 

 upper portions of these young plants. 



The plants with the above features generally attain full 

 development early in the spring, reaching 2-3 feet in height. 

 Then the basal leaves begin to drop off. Late in the autumn, 

 the majority of the basal leaves disappear, and the axial stem 

 elongates considerably, often attaining 15 feet in total length, 

 the lateral branches developing proportionally at the same time. 

 In the vicinity of the Biological Laboratory at Misaki, the 

 receptacles are discharging their contentSr^arly in January. The 

 stems of the matured plants are in the middle and the upper 



