COPEPODA 



119 



second group is represented by a longitudinal row of about 20 minute spines; the third group (cf. 

 PI. IV fig. 3 c) consists of 5 fairly long and slender setae placed more forwards, and lateral, and of 2—3 

 placed more inwards and backwards; the fourth group, which consists of 20—25 fairly strong setae, 

 has a characteristic shape, as it is convex, and has its right and left parts converging towards the 

 middle, and almost touching each other in front; the fifth grotip is a continuation backwards of the 

 fourth, and consists of about 30 more delicate setae. Behind this group an oblique, almost transverse 

 row of short "spines" is observed. Behind the central spot Nr. 3 no transverse row of setae is ob- 

 served, but behind Nr. 4, which is single, two transverse rows of rather delicate setae are observed. 

 The lamina labialis (fig. 3 d), which is distinctly granular, is indistinctly divided into three parts. In 

 front of it, in the middle, is a longitudinal row of short spines on each side, followed by the two areas 

 of acicules, forming a curvature corresponding to the outer row of setae (cf. fig. i c); the latter is single 

 behind, double in front, as a lateral row of shorter setae is found. The arrangement of the spinous 

 areas behind the lamina as well 

 as of the series of hairs on the 

 labial lobes is seen in figs 3 d — e. 



The intestinal tract is 

 almost straight, with a short 

 restriction between the anterior 

 and posterior divisions, and with 

 a slender coecal sac in front. 



fc?. Size of male from 

 Thor St. 88 373 mm.; anterior di- 

 vision 2-92 mm.; urosomeo-8i mm. 



The head has a distinct 

 frontal keel (fig. 3f), somewhat 

 longer and lower than in the 



female; the body is rather elongate, and attenuated in front as well as behind. The head and the first 

 thoracic tergite are completely fused; the articular membranes between the thoracic tergites are like 

 those of the females. The anterior division is 3-5 as long as the urosome; the genital pore is found 

 on the left side of the first abdominal somite; the furcal rami are short, rounded, and about as long as 

 wide; their St. 2 is a little longer than the abdomen, and almost twice as long as the Si. 



The antennulae extend a little beyond the end of the cephalothorax; the segments 2 and 3, 4 

 to 7, 8^9 and 10 as well as 11 to 14 are more or les fused; the segments 20—21 are completely fused 

 on the right side, well separated on the left side. The appendages are Scarcely different from those of 

 E. messinensis; they are as a whole more soft-skinned than in the female, and the Sp. of segment 23 

 is much shorter than that of segment 24. The segment 2 is almost i-i as long as segment 17, which in 

 length is equal to 15, 16 and 19, and about it as long as segments 8<>J9. Segment 20 is on the left 

 side about as long as 80^9, but 20<v2i on the right side combined is the longest segment, and almost 

 1-4 as long as segment 2. The antennae have the Re 1-5 as long as Ri, and have well developed distal setae; 

 the Re I and II are well separated, but the medial tooth of Re I is wanting. The Le of the maxillulae 



Text-fig. 30. Euchirella airticauda Giesbr. 

 a. ft?. Pes II sin. in ant. view x 40. b. f 9. Pes III x c. 40. c. y 9 (stage V). Pes III 

 X c. 40. d. yd" (stage IV, a single specimen from Thor 20/5 1905 vSt. 88 not men- 

 tioned in the text). Pes III sin. X c. 50. e. y9 (St. V). Pes V X 60. 



