94 



PAUL LØYNING. M.-N. Kl. 



fluid was observed to flow in and out of the cerata from the stomach as 

 the latter contracted and extended rythmically. Radula with rarely more 

 than 70 teeth. Living especially on Tubidaria larynx. Mature and singly 

 spawning specimens have been observed from August to Decembei . 



A. olivacea. (A. \- ID Eliot. 



PL III. Fig. 12. 

 New to the Kristianiat'jord fauna. Rather rare. Length up to ic irm. 

 The double red lines in front of and behind the rhinophores very constant. 

 The triangular red spot over the heart on the other hand is most often 

 acking. Cerata often clavated. The colour of the liver-processe' vary 

 greatly from olive yellow to reddish brown. The rings round the cerata 

 which A. & H. quotes as characteristic of the species have never been 

 very clear in the specimens from the Drobak Sound. 



Genus 5. Embletonia. (A. cV II.i. 

 The diagnosis of the genus agrees with Bergh's (1885, p . 33) but with 

 the addition „the mandibles have smooth or denticulated proc. mast." 



E. pallida. (A. & H.i 



PL III. Fig. 13. 

 New to the Kristianiafjord fauna. 1 4 specimens of the species were 

 collected in the autumn of 1920, but have not been observed either before 

 or subsequentl}'. Length up to 5 mm. The form of the buccal bulb very 

 different from that found in the species by other authors. Proc. mast, is 

 definitely denticulated. Radula with remarkably numerous teeth 1 42 — 65I. The 

 form of the teeth is also different. 3 — 4 lateral denticles. Lives on laminaria 

 overgrown with hydroids. Mature individuals not observed, nor spawn. 



Genus 6. Aeolidia. (CuvierI Bergh. 

 Diagnosis of genus as by Bergh 1 1875, p. i.l. 



Aeolidia papillosa. (Linné) Cuvier. 



PL IV. Fig. 14 — 15. 



New to the Kristianiafjord fauna'. Rather rare. Length up to 60 mm. 

 Rows of cerata up to 15. Corners of foot short, blunt. As a rule about 

 20 teeth in radula with 30 — 40 denticles, the middle one of these being 

 some times shorter than the others. Spawn not observed with certaint3\ 

 Lives on algae with hydroids in shallow water. Is often found crawling on 

 stones on the beach. 



Genus 7. Aeolidiella. Bergh. 



Diagnosis of genus like Bergh's 1 1867 p. 99I. 



' See Merknad" in the Introduction. 



