APPENDIX. 209 



APPENDIX. 



THE STRUCTURE OF THE BUD-LIKE ORGANS OF 

 MALTHOPSIS SPINULOSA GARMAN. 



By EMANUEL TROJAN. 



Among the Albatross fishes sent to Professor von Lendenfeld for ex<ami- 

 nation was a specimen of Malthopsis spinulosa Garman. This fish is pro- 

 vided with pecuHar bud-like sense organs, which, on account of their function 

 apparently not being a radiating one, were not described in Professor von 

 Lendenfeld's report. Professor von Lendenfeld entrusted me with the 

 examination of the minute structure of these organs. The results are given 

 below. 



Garman (1899, pp. 106, 107, Plates XXI, XXVI) has described and figured 

 this species. The body is dorsoventrally compressed, the tail has a circular 

 transverse section. Thorn-like scales cover the surface. The lateral line 

 extends along the narrow lateral margin of the body, and is continued on 

 the tail. It appears as a distinct lateral furrow. The margins of this 

 furrow bear fringes. In tlie furrow itself a row of bud-like protuberances 

 is observed. Above and below each one of these a lobular excrescence with 

 fi'inged margin is met with. The fringes of the margins of the furrow and 

 the lobes are composed of fili'form parts, richly pigmented and dark in color. 

 Garman's description and illustrations of the bud-like protuberances are insuf- 

 ficient. He mentions them only from the lateral line and the symphysis 

 below the mouth. Closer inspection shows that they also occur on the head. 

 There are on each side (text figs. 1, 2) : in the lateral line (furrow) of the 

 body 12 ventral (v) ; between the 9 and 10 of the lateral line, one above 

 the other, 2 lateral (1); in the lateral line of the tail 12 caudal (c) ; in a 

 horizontal row behind the corner of the mouth 4 mandibular (m) ; in a line 

 parallel to and above the preceding one 7 maxillary (x) ; between the 4 

 organs of the two last named rows 1 inframaxillary (i) ; and on the lower 

 jaw 4 inframandibular (n) ; together 84 bud-like organs. 



The bud-like organs are cream colored, button-shaped, and composed of 

 a short, stout, cylindrical peduncle only 70 /x long and on a semispherical 

 head 400-500 /x in diameter. The histological structure of these organs can 

 best be made out in longitudinal, axial sections (Fig. 3). The corium is very 

 highly developed and covered by a pavement epithelium with large nuclei as 

 in other parts of the skin. It forms two different kinds of papillae. In the 

 one the corium predominates and the epithelium is only slightly developed, 



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