ON THE SHETLAND CRUSTACEA, TUNICATA, ETC, 803 
Molgqula citrina, Alder & Hancock. Low water, Lerwick, 1861. 
Cynthia coriacea, Alder & Hancock. Dourie Yoe, 1863. 
grossularia, Van Beneden. Common between tide-marks. 
echinata, Linn. ; Ascidia echinata, Forbes & Hanley, vol. i. p. 35, pl. C. 
fig. 4. 5-40 fathoms, Middle Haaf and Bressay Sound, 1863. Para- 
sitic on Ascidia sordida, 5-8 miles east of Balta, 40-50 fathoms, 1867. 
Clavelina lepadiformis, Miller, One mile north of Whalsey Lighthouse, 
1861, 
Polyclinum aurantium, M.-Edwards. 3-5 fathoms, Out Skerries Harbour. 
succineum, Alder, Ann, Nat. Hist. 1863, vol. xi. p.169. The type spe- 
cimen was dredged in 1861, in 50 fathoms, on the Haddock-ground, 6 
miles north of Whalsey Lighthouse. 
Amarecium albicans, M.-Edwards, Obsery. sur les Ascidies Composées, p. 287, 
pl. i. fig. 35. Low water, Lerwick. 
? An undetermined species, tide-marks, Balta Sound, 1863. 
Botryllus and Botrylloides. About ten species observed, but not determined 
satisfactorily. 
Leptoclinum durum, M.-Edwards= Leptoclinum awreum (misprint), Forbes & 
Hanley, vol. i. p. 17. Tide-marks, West Voe, Out Skerries, 1861. 
punctatum, Forbes. With the last. 
Didemnum gelatinosum, M.-Edwards, Obs. Ascid. Compos. p. 295, pl. vii. fig. 5. 
Low water, spring tides, West Voe, Out Skerries; and in Out Skerries 
Harbour, on roots of Laminarie. 
Parascidia Flemivgii, Alder, Ann. Nat. Hist. 1863, vol. xi. p. 172. Sidnywm 
turbinatum, Fleming. Low water, Lerwick. In Mr. Alder’s opinion this 
is not the Sidnyum turbinatum of Savigny (Mém. Anim. sans Vertébres, 
vol. ii. p. 238), nor the Stdnyum turbinatum of Forbes and Hanley, which 
he also considers distinct from Savigny’s species, and proposes to name 
Parascidia Forbesii. 
Salpa runcinata, Chamisso. Both sexual and asexual forms in vast numbers, 
in company with Diphyes and Physophora, 30-35 miles, N.N.W. of 
Burrafirth Lighthouse, July 17 and 18, 1867. 
Appendicularia flagellum, Huxley. Some Appendicularie were taken by me 
in the towing-net in Balta Sound in 1863, which I believe belonged to 
this species; but the bottle in, which they were preserved was unfor- 
tunately lost (I conclude left behind in Shetland), and thus also the 
accurate determination of the species. 
Class POLY ZOA. 
For this class I have adopted, as far as it goes, the general arrangement 
of Mr. Busk, in ‘A Monograph of the Fossil Polyzoa of the Crag, 1859.’ 
This work having been published subsequently to the ‘ Catalogue of Marine 
Polyzoa in the collection of the British Museum, 1852,’ gives us the author’s 
maturer views. With respect to the species, if no reference to other works 
is given, they will be found described in the ‘ Catalogue ;’ but, as will be 
seen by the following Report, our knowledge of the animals of this class has 
been very materially extended since 1852. Herr F. A. Smitt has just pub- 
lished a valuable series of papers on the Polyzoa of the Scandinavian seas, 
entitled ‘* Kritisk forteckning ofver Skandinaviens Hafs-Bryozoer” (Otvers. 
af K. Vet.-Akad. Forhandl. 1865-67), but I am not prepared to acquiesce in 
his views as to the amount of variation to be observed in species of 
the class. 
