462 THE VOYAGE OF H.M.S. CHALLENGER. 



They are uow often out of easy reach, the former floors of the caves having slipped away. 

 They are grouped in all sorts of ways, and amongst them one was seen in which a finger 

 was missing, the native having possibly had a finger cut off as a matter of ceremony. 

 The figure of a whole man is said to exist thus executed, in Cowan Creek, close by. 

 Exactly similar hand marks, made in the same way by the Pueblo Indians, occur in 

 New Mexico in caves in the neighbourhood of the town of Ziini. 



The steam pinnace was frequently engaged in dredging and trawling in Sydney 

 Harbour, and the tow-nets were extensively used. Annelid and Ascidian larvae were 

 especially abundant on the surface, and large collections of Invertebrates were made from 

 the bottom.. Of the numerous forms here obtained none were more interesting to the 

 naturalists than Trigonia (Trigonia lamarckii), a genus of which over a hundred fossil 

 species from Secondary formations of Europe, the United States, parts of South America, 

 Africa, India, &c, are already known. The genus was supposed to be extinct until 

 discovered living in Bass Strait by Quoy and Gaimard, by whom the soft parts were first 

 described. Huxley subsequently gave further details of the anatomy, and Selenka has 

 still more recently published a memoir on this subject. Von Willemoes Suhm, who 

 examined all the recent species known, at the time of his death, thought they might be 

 reduced to four — Trigonia lamarckii and Trigonia strangii 'from Port Jackson and 

 Botany Bay, Trigonia uniophora from the region of Torres Strait, and Trigonia 

 margaritacea ( = Trigonia pectinata) from Bass Strait and Southeast Australia. 

 Besides these there is in the Sydney Museum (in single valves) a Trigonia showing 

 very large tubercles on the radiating ribs like some of the fossil forms, which appears to 

 be undescribed. Since von Willemoes Suhm made the above notes another species 

 {Trigonia acuticostata), which was previously only known as a Miocene fossil, has been 

 dredged alive in Bass Strait. 



Several specimens of the Port Jackson Shark (Cestracioti philippi) were also procured, 

 and it is interesting to note that the remains of a closely allied Plagiostomous fish have 

 been found in Secondary deposits along with Trigonia. 



Von Willemoes Suhm says : — " The Phyllopods got at Sydney belong to the genera 

 Limnetis and Limnadia, and are especially interesting because of Limnadia, found in 

 some places in Europe, is constantly parthenogenetic, the male being known only from 

 the Australian species, as described by Claus. Kreeft says that males and females are 

 constantly found together here, except in the wet season, as now, when no living animals 

 but only some shells, could be got." 1 



The Challenger remained at Sydney from the 6th April to the 8th June, as the ship 

 required docking and a general overhaul, and during this time the members of the 



1 A Dipterous insect was obtained by von Willemoes Suhm, which has been lnaile the type of a new species, 

 Vcuypofjon diversipes, Kirby {Ami, and Mag, Xat. Hist., ser. 5, vol. xiii. p. 458, 1884). 



