92 
Gustaf T. Troedsson 
Primitia harparum n. sp. 
PI. II, f. 4—5. 
The dorsal margin straight, making an obtuse angle with the anterior one, which 
rather abruptly curves downwards to the ventral margin; posterior ventral angle 
gently rounded. Carapace highest in the middle or a little more forward. The sulcus 
is on its anterior side provided with a rounded prominence and mostly curved, 
having an oblique direction against the anterior ventral angle. In the upper third 
of the valve it is broad and deep and then it gently effaces forming a broad de- 
pression and extending below the middle of the shell dividing it into a posterior 
and an anterior part, the former being the greater and the more convex. Marginal 
border lacking. — This species is the biggest ostracod of the Brachiopod beds. 
For the measures see p. 48. 
Primitia conica n. sp. 
Pi. II, f. 6—7. 
Carapace broadly ovate, with straight dorsal margin half as long as the shell. 
Convexity slightly conical, highest on each side of the sulcus. This is situated 
a little before the middle of the valve and extends from the dorsal margin to a 
third of the val^e or half of it. It is thin and shallow almost vertical hut sometimes 
it runs obliquely forwards, straight or' curved. Near the middle of the valve the 
furrow is strongly marked, but sometimes in its upper part it is wholly effaced. 
Surface minutely punctate which mostly is to be seen in the moulds. A few specimens 
show a line-shaped impression running parallel to the ventral margin but a fair bit 
inside. — Some specimens have a longer dorsal margin and a lower convexity. 
On the interior cast, the most common state of preservation of this fossil, the 
sulcus is more pronounced and always curved forward at least in its lower part. Its 
anterior wall is more abrupt than the posterior. The parts of the valve lying be- 
hind or before the sulcus are apparently swollen. For the measures see p. 49. 
Primitia bursa Krause var. scanensis n. var. 
PI. II, f. 8—10. 
This variety differs from P. bursa by its larger size, more rounded ends and 
the continuing of the marginal border a good way into the dorsal margin. Two 
types are to be distinguished, a high one and a low one. They may indicate 
male and female but the difference is not 4 clearly distinct. For the measures 
see p. 50. 
