WIDERSTEN: ANTHOZOA FROM EASTERN COAST OF UNITED STATES 



of the column varies between 8 and 18 mm, whilst 

 the diameter of the pedal disc is 12-20 mm. The 

 column is greyish, salmon-colored and divisible 

 into scapus and scapulus. The scapus is provided 

 with distinct mesenterial insertions shimmering 

 through the ectoderm and has small tenaculi. The 

 tentacles of the studied specimens are about 9 mm 

 long, conical and acute. They are hexamerously 

 arranged; in the largest specimen there are five 

 cycles (6 -I- 6 -I- 12 -1-24 -I- 40). The reddish-brown 

 actinopharynx is strongly folded and provided 

 with two siphonoglyphs. The color of the tentacles 

 is greyish white, the largest specimen with red- 

 dish-brown pigmentation. The pairs of mesente- 

 ries are arranged in four to five cycles (proximally 

 there are 90-100 mesenteries— distally only half 

 the number are developed). The number of perfect 

 mesenteries tends to vary. In one of the studied 

 specimens there are 17 pairs (including the two 

 directive pairs). The first cycle of mesenteries is 

 sterile. The retractors of the first cycle of mesen- 

 teries are strong, of a circumscribed diffuse type 

 (Figure 7A); in the other mesenteries they are 

 diffuse. The parietobasilar muscles are rather 

 weak (Figure 7B). The acontia are numerous and 

 whitish in color. The mesogloeal, diffuse spincter is 

 rather long. 



NEMAT0CYSTS.-5m/>ws: basitrichs 9-11.5 x 

 1.6, 16-17 X 2.2-3.3; microbasic amastigophors 

 30.5-35 X 4.4, ca. 15 x 3.8 (rare). Tentacles: basi- 

 trichs 13 X 2.2 - 27 X 2.7; microbasic amasti- 

 gophors (16 X 3.8-) 26 X 4.4 - 44 x 6.5; spirocysts 

 22 x 3.8 - 36 X 6. Actinopharynx: basitrichs 27- 

 32 X 3.3; microbasic p-mastigophors ca. 23 x 4.4, 

 27-31 X 4.4-4.9. Filaments: basitrichs (rare) ca. 

 27 X 3.8; microbasic p-mastigophors 26-31 x 

 4.4-4.9; spirocysts 22 x 4.9 - 34 x 6. Acontia: 

 basitrichs 36.5 x 3.8 - 43 x 4.4-4.9; microbasic 

 amastigophors 57 x 6 - 64 x 7.1 jum. 



Hormathiidae 



Hormathia nodosa (Fabricius 1780) 



OCCURRENCE.-40°54'N, 66°35'W, 265 m, 4 

 specimens; 41°30'N, 69°00'W, 146 m, till, 1 

 specimen; 42°14'N, 69°57'W, 102 m, 1 specimen; 

 42°26'N, 66°28'W, 265 m, gravel, 8 specimens. 



GENERAL CHARACTERISTICS.-The 9-28 

 mm high scapus is provided with white tubercles 

 arranged in longitudinally oriented rows. The 



etrent 



B 



Figure l.-Saqartiogeton rerrilli. A. Section of the retractor of a 

 perfect mesentery with adjacent parts of the actinopharynx. 

 B. Section of the peripheral part of a mesentery (from the distal 

 part of the scapus). ent— entoderm, mgl— mesogloea, retr 

 ent-entoderm of retractor muscle. 



scapular ridges are white and are 12 in number. 

 The scapus is covered by a thin, greyish-white to 

 greyish-brown periderm and is equipped with 

 shallow longitudinal as well as transverse furrows; 

 on the edge of the scapulus only radiating furrows 

 are seen. The diameter of the column is 12-33 mm 

 (diameter of scapus: diameter of the pedal disc = 

 ca. 3:4). The tentacles are conical, reddish brown, 

 and in older specimens longitudinally furrowed. 

 They are 96 in number. The mesenteries have a 

 maximum of 48 pairs (6-1-6-1-12-1-24), 6 of which 

 (including the 2 pairs of directives) are perfect and 

 sterile. The anatomical characters agree with 

 earlier descriptions (cf. Carlgren 1893, 1933; Verrill 

 1922). 



NEMATOCYSTS.-Scapws: basitrichs 8 x 1.1 - 

 11 X 1.6, 21-24 X 3.3-3.8; spirocysts 17 x 3.8 - 

 25 X 4.4. Tentacles: basitrichs 17 x 2.2 - 34 x 

 3.8; spirocysts 23 x 3.3-4.4 - 44 (56) x 5.4-7.6. 

 Actinopharynx: basitrichs 16 X 1.6 - 35 X 3.3- 

 3.8; microbasic p-mastigophors 23-33 x 3.8. Fila- 



871 



