22 



er efter mine erfaringer antallet af stigmarækker hos den 

 første gjeniienigaaende lavere end hos den sidste, medens 

 derinidd antallet af stigmata inden hver 1'ække er høiere 

 hos botnjihis end hos botn/Uoides. Dette er l)lot en natur- 

 hg folge af individernes hos Ijotrylloidesgruppen cylinder- 

 formige langstrakte, hos Ijotryllusgriippen kortere og mere 

 sammentrængte bygning. 



Ovennævnte 4 subgenera, om hvis berettigelse der 

 kan lierske beføiet tvil. vil jeg i mangel af nbget bedre 

 indtil videre fastholde af hensyn til botryllusslægtens form- 

 rigdoni. 



Af botrylloider iiar jeg fundet 6 arter, hvoraf 2 til- 

 hørende slægten botryJhis, 1 folycydns, 1 hotryUoides og 2 

 aarcohotrylloides. 



Botryllus, Goertnei-, 1774. 

 Botryilus marionis (?), Giard, 1872. 



(Tab. IL fig-. -Jfi). 

 1872. Botryllus marionis, Giard. Recherclies snr les Ase. 



comp. ou Synasc. Arch. Zool. 



exper. t. I. 

 Kun en eneste li(li'n koloni: 4 cm. lang, 8""" bred og 

 1 — 1. .'.""" tyk, omvoxendo en alge. Individernes størrelse og 

 farve svarede i alt væsentlig til (_Tinvds l)eskrivelse: kun var 

 der, istedenfor den paa individernes overside afgatte hvide 

 flæk, 2 noget kortere jiaiallrlt Inliende streger af samme 

 farve. Med sikkerhed at identiticere den fundne art nn-d 

 b. nmrionis, Giai-d, lader sig dog ikke gjøre, da forfatterens 

 l)eskiivelse er baseret alene paa farven. Foreløbig vil jeg 

 henføre den fnndne coinuis til ilennc art, saa meget mere 

 som denne genus tidligere er overfyldt med nærstaaende 

 ufuldstændis beskrevne arter. 



De øvrige artskarakterer er: 

 Systemerne: circulære eller svagt ellipsformige. 

 Tentaklerne: 16 i antal, hvoraf de 2 laterale lange og 

 smale; de øvrige ganske korte og af samme længde. 



Branchialsækken med 7 — 8 rækker stigmata. Form- 

 len: d. 6 — 4—4 — 6 v. 



Æggene talrige og relativt store. 



.Arten blev funden i en dybde af 4 favne i Eoalds- 

 fjorden ved Bømraeloens sydende (juli). 



Botryllus violaceus (?), Milne-Edwards, 1842. 



(Tab. II, fig. -11). 



1842. Botryllus violaceus, M.-Edw. Mem. de Tac. roy de 



SC. tom. XVIII. 

 1872. — — Giard. Recherches sur les Ase. 



comi3. ou Synase. Arch. Zool. 



exper. t. I. 



of rows of stigmata in the former is, on an average, 

 smaller than in the latter, vvhile on the other hand, the 

 number of stigmata in each row is larger in Botryllus than 

 in Botrylloides. This is only a natural consequence of the 

 elongated, cylindrical strueture of the members in the Bo- 

 trylloides group, and of the shorter and more compressed 

 strueture of those in the Botryllus group. 



The above 4 genera, as to whose legitimacy justifi- 

 able doul>t may prevail, I shall, for want of anything better, 

 retaiu for the present, on account of the wealth of form 

 in the genus Botiyllus. 



I have found 6 species of Botryllidæ, 2 l)elonging to 

 the genus Botryllus. 1 to Polycydus, 1 to Botrylloides and 

 2 to Sarcobotrylloides. 



Botryllus, Goertner, 1774. 

 Botryllus marionis (?), Giard, 1872. 



(Pl. II, fia:. 2(i). 

 1872. Botryllus marionis, Giard. Recherches sur les Ase. 



comji. ou Synasc. Arch. Zool. 

 ex])er. t. I. 



Only onc little colony was found. measni'ing 4 cm. in 

 length, 8""" in breadth. and from I to 1 ..'i'"'" in thickness, 

 .investing sea-Aveed. The size and colour of the members 

 eorresponded in all essential respects witii Giard's descrip- 

 tion, except that instead iif the oue white spot on the 

 upper side of tiie member, there are two somewhat siiorter 

 parallel streaks of the same colour. It is not however 

 possible to indentify, with any certainty, the species found 

 with B. marionis, Giard, as that writer's description is 

 based on the colour alone. For the present I will refer 

 the above cormus to tliis species, the more readily as this 

 genus was formerly overfillcd with nearly-ailiod, incomplete- 

 ly-deseribed species 



Tiie remaining specific eharacters are: 



Systems circular or slightly elliptical. 



Teutacles 16 in number, the 2 lateral ones being 

 long and narrow, the remainder quite short and of equal 

 length. 



Branchial sac with 7 or 8 rows of stigmata. For- 

 måla, å. 6 — 4 — 4 — 6 r. 



Ova nunierous and relatively large. 



The species was found in July at a depth (jf 4 fathoms 

 in Roalds Fjord, at the south end of Bømmeløen. 



Botryllus violaceus (?), Milne-Edwards. 1842. 

 (Pl. II, fio-. -27). 



1842. Botryllus violaceus, M.-Edw. Mem. de FAc. roy. de 



se. tom. XVIII. 

 1872. — — Giard. Reclierches sur les Ase. 



comp. DU Synasc. Arch. Zool. 



exper. t. I. 



