82 



and basal margins meeting at the umbo and forming a sharp angle projecting beyond the line 

 of the carina. The lateral and upper margins are of about the same length and meet at a very 

 obtuse angle. In the specimens with imperfectly calcified valves, the calcified part has the form 

 of a Chinese boot, the part that is not calcified having the shape of a rectangular triangle. 



The peduncle is cylindrical and shows 8 to 1 2 longitudinal rows of scales. In the 

 specimens with perfectly calcified valves these scales are perhaps distributed slightly more 

 regularly than in the others. 



Size. The specimens figured measure 20, 19 and 26,6 mm.; their capitulums 13,3, 13,8 

 and 16,2 mm. 



The study of the structure of the animal contained within the capitulum has yielded the 

 following results : 



Mouth triangular when seen from above, slightly bullate. L a b r u m with hardly 

 ■distinguishable teeth; palpi conical, rather pointed at the extremity, with short and not 

 numerous hairs, those on the apex little longer. 



Mandibles with three teeth, which are pointed at the extremity and slightly swollen 

 a little before the extremity; the inferior angle is blunt and furnished at the under side near 

 the extremity with about four triangular, small, sharp teeth. Teeth 2 and 3, and 3 and inferior 

 anele at shorter distances from one another than teeth i and 2. Near the inferior angle the 

 surface bears a few very delicate hairs placed in groups of three or four. Along the under 

 margin are planted short hairs. 



Maxillae rather narrow; edge with a very distinct notch, a little above the middle; 

 three strong spines, of which the first is the strongest, above the notch ; one spine in the notch 

 and 7 to 8 rather strong spines, which do not differ much from one another in strength, beneath 

 the notch. The surface of the maxilla bears delicate hairs, partly in groups, on the distal 

 extremity only. Apodeme broad, not very long. 



Second maxillae of the ordinary shape, with hairs along the outer and inner side 

 and also at the apex; a long tubular process, which is flat and truncated at the extremity, gives 

 entrance to the body cavity. 



Cirri. First pair at some distance from the second pair; rami unequal: the anterior 

 shorter and broader, the posterior longer and narrower. Both rami have a long basal segment, 

 which is indistinctly divided into smaller segments; the short ramus has moreover 4, the long 

 ramus 8 distinct segments. Along the sides of the more or less flattened segments stout spines are 

 planted on knobs ; more slender spines or hairs are scattered all over the surface of the segments. 



Second cirrus with about 20 segments in each ramus; the first setrment is long and 

 consists of several segments fused together ; the following segments short, quadrangular, gradually 

 growing longer, the last being as long as the foregoing ones but considerably narrower. Spines 

 on the anterior side .stouter and planted on knobs : four pairs on each segment as a rule ; those 

 on the posterior side more delicate, less numerous and not placed so regularly. 



Sixth cirrus having in each ramus a long basal segment consisting of several segments 

 fused together and about 25 clearly distinguishable segments. These grow gradually longer and 

 narrower from the base to the extremity. Each segment bears, as a rule, 4 pairs of long spines 



