l82 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I28 



With the exception of Rhizomolgula, the most abundant simple 

 ascidian was undoubtedly Boltenia echinata (Linnaeus) with its cream 

 tunic tinged with red, especially around the apertures. Externally it 

 resembles a cactus. From a few to many individuals were present in 

 all hauls from no to 453 feet. One small stone from 217 feet had 

 five echinata on it. Usually attached to stones, it may be found also 

 on bryozoans and other animals. Young specimens up to 15 mm. 

 were attached to Porclla compressa. Numerous individuals were 

 searched for parasitic copepods and a total of 10 specimens of a new 

 species of Doropygus were found. Boltenia echinata represents a new 

 host for this genus of copepod. In a specimen of Boltenia 17 mm. 

 high taken on October 11, 1949, at 453 feet the ovaries and testes were 

 about half developed. 



Not far behind the above species in abundance was Boltenia ovifera 

 (Linnaeus), also present in all hauls from no to 453 feet. Specimens 

 with stalks up to 170 mm. long were taken. B. ovifera is found at- 

 tached to rocks, bryozoans, other tunicates, and to old holdfasts of 

 hydroids and bryozoans. Occasionally large clusters of small to 

 medium individuals with intermingled holdfasts and stalks were 

 brought up. Out of 63 individuals examined on October 14, 1949, 4 

 contained the parasitic copepod Schisoproctus inflatus Aurivillius. 

 Two copepods were taken from 26 tunicates from 453 feet, and one 

 young copepod came from a small tunicate from 341 feet. This 

 species appears to have no definite breeding season. Specimens ex- 

 amined on October 11, 1949, had gonads in various combinations of 

 development, some with full testes and fairly full ovaries, others with 

 empty testes and full ovaries ; in others both testes and ovaries were 

 developing, and in still others one testis might be small, the other, half 

 developed, and the ovaries fairly well developed. 



The largest and most conspicuous, but far from the most plentiful, 

 tunicate was Halocynthia aurantium (Pallas), with its flesh-white 

 tunic with traces of yellow and with a deeper flesh-pink color on one 

 side. From one to several specimens were taken in hauls from no 

 to 217 feet. It is new to Point Barrow. 



Perhaps often overlooked because of its small size, its transparency, 

 and its habitat, Molgula griffithsi (MacLeay) was abundant at Eluit- 

 kak Pass and in hauls from 1 18 to 477 feet. It was commonly attached 

 to the hydroid Lajoeina maxima which was also abundant, to other 

 hydroids, and to bryozoans such as Barentsia, Eucratea, and Dendro- 

 beania. At 477 feet it was attached to the tubes of Pista. Small as 

 this species is, one individual had a species of Tubularia (hydroid) 



