76 DR. H. J. HANSEN ON CRUSTACEANS [Jan. 20, 
luminous points in recently sieved bottom material from 
318 fathoms, and undertook instantly some manipulations with 
the animals: the luminous fluid came from the head, probably 
from the large labrum, and flowed backwards between the shells, 
illuminating brilliantly the space between them, especially on the 
ventral side. As to the Entomostraca, we can therefore not speak 
of “luminous organs” in the common sense of the word, the light 
being always produced in the above-described way. 
In almost all Euphausiide real and highly-developed luminous 
organs are found, but they differ in structure very much from 
those in Serg. challengert. The reader is referred to Sars’s 
Report on the ‘ Challenger’ Schizopoda, and to Chun, “‘ Leucht- 
organe und Facettenaugen” (Bibliotheca Zoologica, Heft xix. 
lief. 4, 1896). The highest number of organs met with in this 
family is only ten: one on each eye-stalk, two on each side of the 
thorax near its inferior margin, and one in the median line of 
each of the four anterior abdominal segments. The light is 
produced by the “Streifenkérper ” (Chun)—“a flabelliform bunch 
of exceedingly delicate fibres, exhibiting in fresh specimens a most 
beautiful iridescent lustre” (Sars, op. cit. p. 71)—situated a little 
behind the centre of the organ in a mass of large cells; a biconvex 
lens, which is present in the organs with the exception of those on 
the eye-stalks, is internal, while the outer chitinous skin is thin ; 
a reflector is developed nearly as in Sergestes. 
The Danish zoologist Cand. mag. Ad. 8. Jensen has directed 
my attention to a book by a French author, and lent me a 
German translation: ‘ Die Leuchtenden Tiere und Pflanzen. Von 
Henri Gadeau de Kerville. Aus dem Franzosischen tbersetzt 
von W. Marshall, 1893.’ In this popular treatise I saw that the 
‘Talisman’ had captured a deep-sea shrimp with numerous 
luminous organs. I attempted in the ‘ Zoological Record’ and 
elsewhere to discover where that animal had been described, but 
in vain, and [ will therefore reprint the passage in question from 
the German book :—‘‘ Wahrend der wissenschaftlichen Hxpedi- 
tionen des Talisman fing man in einer Tiefe von 500 m. einen 
langschwinzigen Krebs (Acanthephyra pellucida A. Milne- 
Edwards), welcher ein lebhaftes Licht um sich zu verbreiten 1m 
stande war und zwar mittels folgender verschiedener Leucht- 
organe; erstens befand sich eins am Vorderrand einer Deckschuppe 
der Augen, zweitens verlief eine lange leuchtende Linie am 
Aussenrand des Tarsus des fiinften Beimpaares, an dessen innern 
Basis sowie an der des vorhergehenden Beingliedes sich weiter 
leuchtende Flecke befanden, drittens lagen ganz ahnliche Flecke 
an der Basis des zweiten Gliedes des dritten und vierten Bein- 
paares und ebenso je einer an der Basis des Tarsus derselben 
Gliedmassen, viertens sah man einen langen Fleck an der Basis am 
Endgliede des hintersten Kieferfusspaares, fiinftens verlief ein 
schimmerndes Querband tuber die Hiifte des hintersten Thorakal- 
fusspaares, sechstens war eine Doppelreihe glanzender Punkte an 
jedem Gliede der Aussengeissel der Brustfiisse, sowie an dem 
ausseren Blatt der Bauchfiisse vorhanden, siebentens zeigte sich 
