. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. NEMERTEANS 271 dilated or very capacious and full of nucleated corpuscles. This appears to be a constant character of the species, though it does not always appear in life in the marked form shown in Plate XVI, fig. 23. The cerebral organs are very small and far in front of the brain. The relative positions of the brain, cerebral f-jpr organs, eyes and head glands can be seen in the graphic reconstruction (Fig. 47). The anterior caecum has no forward branches and lies far behind the brain. The b
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. NEMERTEANS 271 dilated or very capacious and full of nucleated corpuscles. This appears to be a constant character of the species, though it does not always appear in life in the marked form shown in Plate XVI, fig. 23. The cerebral organs are very small and far in front of the brain. The relative positions of the brain, cerebral f-jpr organs, eyes and head glands can be seen in the graphic reconstruction (Fig. 47). The anterior caecum has no forward branches and lies far behind the brain. The brain is large, the dorsal ganglia being about equal in size to the ventral and continuing into the lateral nerves down the body. I have not been able to identify this form with any known species although it approaches T. belgicae, Burger, 1904a. Tetrastemma georgianum, Burger, 1893 (Plate XVI, figs. 2, 13; Fig. 48). This species was first noted from King Edward Cove. Two specimens were taken in September and four in October 1925, from kelp roots. A single speci- men occurred at St. WS 65 in Undine Harbour. The smallest worm was 3-5 mm. long, but the usual length was from 10 to 15 mm., breadth 0-7 mm. The original sketch and description were made from six specimens (N 7). In 1929 a single specimen was collected in the Fi8- 47- Tetrastemma esbenseni, , 1 • it- t^j j r> i_ • 1 -j sn j Graphic reconstruction of the head and dredge in King bdward Cove which was identified . c , , , , , 0 ° anterior end 01 the body, co, cerebral later with a larger form described under N 15, no organ;*, anterior eye -hg, head glands, differences being found in sections. The size attained may be 25-0 mm. Other captures were made—three specimens at St. 123, one at St. 140 and one at St. 51 (identified from sections, N 126). Form and colour in life. The head is somewhat round in outline from above, but the snout has a median vertical cleft. The body is broadest at about half its length a
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