NARRATIVE OF THE CRUISE. 195 



dition. • The finer and smaller fragments were almost wholly made up of broken pieces 

 of larger shells. The small specimens and primordial chambers, so common in shallower 

 deep-sea soundings, were nearly absent. In the same way Ehabdoliths were not com- 

 plete, if present at all, and the Coccoliths were very minute. The mineral particles 

 in the soundings along the African coast sometimes reached 0'7 mm. in diameter, but 

 in Mid Atlantic they seldom exceeded 0'05 mm. Quartz and glauconite were prate 1 1 1 

 only in the deposits near the African continent, the mineral particles in the other 

 deposits consisting of fragments of felspars (sanidine), magnetite, hornblende, and glassy 

 rocks. Eadiolarians, Diatoms, Sponge spicules, and arenaceous Foraminifera never made 

 up more than 3 per cent, of the deposits, which were of a red or rose colour, except in 

 a few of the soundings near the African coast, where they had a black or slate colour, 

 owing, apparently, to the presence of fine mud or river detritus. 



Pelagic organisms were very abundant at or near the surface throughout this trip, 

 and the sea was brilliantly phosphorescent, especially on the evenings of the 14th and 

 16th August, off the African coast. The trawlings at 2500 fathoms and 1850 fathoms 

 yielded many interesting deep-sea species, some of which are referred to in the following 

 notes. 



Balanoglossus. Dr. v. Willemoes Suhm writes as follows: — "Station 101, 19th 

 August 1873, 2500 fathoms. Among the worms there is a fragment of Balanoglossus. 

 Originally discovered by Delle Chiaje in Naples, this worm 

 remained unknown for a long time, until Kowalewsky came to ^ \, 



that place and made astonishing discoveries in its anatomy, C-^^fe§* t 



showing that Balanoglossus is an animal in which the beginning ^Tmt 



of the intestinal tube is in connection with a branchial apparatus Iff HI \ 

 similar to that which is found in Ascidians. There are, besides, 1 \\\ j 

 so many peculiarities in the structure and anatomy of Balano- mYB 



glossus, that Gegenbaur established for it a special order among I I 



the class of worms. The interest in Balanoglossus was subse- 9wfftm « 



quently increased when, four years ago, Metschnikoff published Fro 7g _ Fragment (head) of 

 a paper in which he stated that Tornaria— the larva discovered £"Htedi.^!2» 

 by Joh. Midler, and since that time believed to be an Echino- 2 o' w. f depth, 2066 fathoms ; 



i 1 n.ii r r> 1 7 1 A a1 «> proboscis; b collar-like 



derm-larva — was really the larva ot Balanoglossus. Another neck ; c, body ; d, walls of the 



„ ii- • • i a a • branchial apparatus ; e, median 



paper confirmed this supposition, and quite recently A. Agassiz vessel. From a drawing by v. 



f i • • • r> 7 7 Willemoes Suhm. 



has shown more fully, in an American species of Balanoglossus, 



the metamorphoses which Tornaria undergoes. 3 Two additional species are known 



from Naples, and one from Hellebek near Copenhagen. The one we got to-day was 



1 Nachricht. v. d. Qe.org.-Awj. Univ. zu Obttingen, No. 15, p. 28V, 1869. 



2 Zeitschr.f. u-iss. Zooi, BcL xx. pp. 131-144, pi. xiii., 1870. 3 Amer. Acad. Mem., vol. ix. pp. 421-436, 1873. 



