KOPOID AND SWEZY: UNARMORED DINOPLAGELLATA 129 



the presence of ^1. roti(ii(hifi(iii in the White and Barents seas. A number of 

 species have been recorded from tlie Baltic Sea and off the coast of Norway 

 and Sweden. Of these Lohmann (1908) found A. longum, A. crassum, and 

 A. rofundatum at Kiel, Germany; Lemniermann (1896Z>) described A. ovoideum 

 in brackish waters near Plon, Germany; and Stein (1883) figures A. steini from 

 Wismar, Germany. A. opcrculatum has been recorded by Claparede and Lacli- 

 mann (1858-61) from the southwest coast of Norway, by Cleve (1884) from 

 the west coast of Sweden, and by Calkins (1902) from the Atlantic at Woods 

 Hole, Mass. 



The only species recorded from the Mediterranean are A. kid si by Klebs 

 (1884) from the Bay of Naples and .4. lance ol at urn by Schroder (1911) from 

 the Adriatic. The only species thus far rej)orted from the Pacific is A. sidcatum 

 by Kofoid (1907r0 off San Diego. 



To this single record for the Pacific we add in this paper from the plankton 

 and sandy beach off La Jolla, California, the following twelve new species: 

 A. asymmetncnm, A. corpuloitum, A. cucurhitdla, A. cucurhitn, A. deHtatiun, 

 A. fastigium, A. paci'ficum, A. gnlhanum, A. scissum, A. truncatum, A. turho, 

 and A. vasculum. 



A single species, A. lacustre, has been described from fresh-water pools near 

 Prague, Austria, by Stein (1883\ Schilling (1913) records the finding of this 

 species in brackish waters in Hungary by Daday. 



Ampludinimn is chiefly a littoral or shore form, but a few species have been 

 described from deeper waters. Six of these are from the Pacific and are the 

 largest species in the genus. A. cucurhifa and A. cucurhitella were found only 

 at 1.5 to 6 miles offshore, from a depth of 80 meters, and A. sidcatum in a haul 

 from 165 meters 10.5 miles offshore. A. opcrculatum has been recorded both 

 from deep waters and from a sandy beach, the latter observation made by 

 Spengel at Norderney, Denmark, and recorded by Bergh (1882). Herdman 

 (1911, 1912) found A. licrdmani with several unknown species of Amphidiuium. 

 in vast quantities on the sandy beach at I^ort Erin, Isle of Man. The species 

 found on the sandy 1)each at La Jolla, on the Pacific coast, are A. scissum, A. 

 asyrnmetricum , A. corpulentum , A. dentatwm, and A. truncatum. 



The seasonal record of the appearance of the species of this genus is only 

 fragmentary. Many of them are present throughout tlie year. Calkins (1902) 

 found A. operculatum. common at Woods Hole, ]Mass., from July to September; 

 Bergh (1882) records its presence in enormous masses on the beach at Norder- 

 ney, Denmark, in December and January. Lohmann (1908) found A. rotun- 

 datum and A. crassum present in the Baltic Sea at Kiel throughout the year. 

 Tlie latter species Lebour (1917rO found from June to September at Plymouth 

 Sound, England, and .4. r(jtuud(dum was recorded from tlie White and Barents 

 seas in June and July by Mielck (1914). .4. klchsi was recorded by Klebs 

 (1884) from the Bay of Naples in the early spring months. .4. herdmani was 

 found in vast numbers at Port Erin, Isle of IMan, from April to November hv 

 Herdman (1911-13). 



