Pbbbuary i, 1916] 



SCIENCE 



181 



to splaBChnic motor niduli. Secondarily by mi- 

 gration (neurobiotaxis) tliese relations are re- 

 versed as in mammals (Graeper, '13). 



The connection of four rhombomeres with a 

 single visceral arch (the hyoid), and of three vis- 

 ceral arches with a single rhombomere (the 

 seventh) is a fact not easily reconciled with the 

 assumption that a single rhombomere was orig- 

 inally connected by a splanchnic motor nerve with 

 a single visceral arch. 

 The Spines of Catfishes (illustrated with lantern) : 



H. D. Eeed and T. J. Lloyd, Cornell University. 



The following observations upon the spines of 

 catfishes were made chiefly upon the pectoral fins 

 of Ameiurus nebulosus and various species of 

 Schilbeodes, and are incidental to another study. 

 In an attempt to determine the morphology of cer- 

 tain soft parts of the fins of catfishes it became 

 obvious that there existed a definite relation ',0 

 the morphology of the spines. A search of the 

 literature revealed only such statements as "the 

 spines are believed to represent a fusion of soft 

 rays" rather than the ankylosis of the lepido- 

 trichia of a single soft ray as in the true spiny- 

 rayed fishes. 



A study of the mature spines and developmental 

 stages shows that the spines of the catfishes ex- 

 amined represent a fusion of several soft rays. 

 The rays contributing to the formation of spines 

 arise in the typical fashion and the fusion of rays 

 as well as the lepidotrichia is from the base toward 

 the free end. The cavity of the spine represents 

 the distal (cephalic) half of the space found 

 normally between the individuals of the fused 

 pairs of lepidotrichia. The last ray, in young in- 

 dividuals, at least, is free for its distal half where 

 it is segmented and bifurcates, as do the unmodi- 

 fied soft rays. 



MISCELLANEOUS 



A New Method of Observing the Bronchial Tree 



of the Embryonic Lung : Wm. A. Loot and Olop 



Lassell, Northwestern University. 



The diifieulties of observing early stages of the 

 bronchial tree of the embryonic lung are consider- 

 able. Wax reconstructions, celloidin injections 

 and Wood's metal casts have unfavorable limita- 

 tions. 



A simple method is now available by the modi- 

 fication of a method of an injection originated by 

 Hochstetter in 1898, for study of the semicircular 

 canals of the ear. The lungs are dissected out 

 of fixed and hardened specimens and cleared in 

 thick cedar oil, after which they are immersed in 

 a mixture of one part thick cedar oil and two 

 parts chloroform. After thorough penetration, the 

 specimen is removed from the mixture and placed 

 on a filter paper until the chloroform evaporates. 

 This serves to draw the cedar oil from the various 

 branches of the bronchial tree and to fill the spaces 

 with air. When the air-filled preparation is im- 

 mersed in pure cedar oil the entire bronchial tree 

 presents the appearance of being filled with a 

 bright metallic cast and can be readily observed 

 through the translucent walls of the lung. The 

 minuter air passages are permeated, and, although 

 the smallest ones disappear in a few minutes as the 

 cedar oil percolates into them, the same specimen, 

 if carefully manipulated, can be treated repeatedly 

 without apparent injury. Results of this method 

 are illustrated by lantern slides. 

 The Parasitic Fauna of the Bermudas: Peanklin 



D. Barker, University of Nebraska. 

 The preliminary study of the animal parasites 

 collected in the Bermudas during the summer of 

 1912 has been completed. A brief summary of the 

 parasites found is as follows: 



Number of Speclea Found 

 1 



Host 



.Toad 



Parasite 



1. Protozoa 



2. Trematoda 



A. Encysted 2 2 species of fish 



B. Ectoparasites 2 9 species of fish 



C. Endoparasites 44 23 species of fish 



" 2 2 species of sea-cucumber 



3. Turbellarias endoparasites 



4. Cestoda 



A. Mature 



B. Immature (free) 



C. Immature (encysted) 



5. Nematoda 



A. Mature 



B. Immature (free) 



C. Immature (encysted) , 



6. Acanthocephala 3 7 species of fish 



7. Crustacea 



A. Copepoda Undetermined 10 species of fish 



B. Isopoda Undetermined 5 species of fish 



2 6 species of fish 



5 14 species of fish 



3 7 species of fish 



3 10 species of fish 



2 5 species of fish 



