162 MB. F. M. CAMPBELL ON THE 



DESCRIPTION OF THE PLATES. 

 Plate V. 

 Fig. 1. Fiingia echinata. Fracture across the coral, showing palisade-like septa, 

 cribriform septa, perforations in the base-wall, and long curved synap- 

 ticula. X 2. 



2. Ditto. The same, with imperfect synapticula. X 2. 



3. Fimgia scufaria, Tar. Fracture across the coral, showing strong nearly 



vertical and curved synapticula and solid and cribriform septa. 



4. Section tangential to the circumference of the same specimen, showing 



the synapticula cut across in various parts of their course. 

 6. View of surface of coral, showing the tops of the synapticula in the 

 interseptal loculi. 



6. The direction of the ultimate fibrous structure in a cribriform septum. 



X300. 



7. The direction of the fibres in a septum and synapticula on either side ; 



the dark wavy lines are connective tissue. X 300. 



8. Part of the end of a septum with fibres resolved into crowds of spi- 



cules; tubes oi Achlya penetrans, nobis, are parasitic. X 400. 



Plate VI. 

 Fig. 1. Halomitra Crustacea. The corallum. 



2. Fracture removing one septum from its neighbour, showing perforate 



base-wall, upright stout synapticula joining together by cross pieces; 

 above are the ornamental granules of the free septal edge. X 3. 



3. Another view, showing a stout massive sj-napticulum. X 3. 



4. Part of a calice, showing synapticula from above. X 2. 

 6. The perforated base, from below. X 2. 



6. Herpolitha limosa, A fracture, showing synapticula and basal perfora 



tions. 



7. Synapticula, seen from above, between granular septa. 



8 T 

 • Microscopic views of the spicules of Fungia sctitaria, var. X 600. 



[ Diameter of spicule -^^tsts inch. 



On the Pairing of Tegenaria Guyonii, Guer., with a Description 

 of certain Organs in the Abdominal Sexual Eegion of the 

 Male. Bj P. Maule Campbell, P.L.S. 



[Eead February 1, 1883.] 



(Plates VII. & VIII.) 



Pairing or Tegenaeia Gutonii (Gtier.). 



The relation between the palpi and abdominal sexual organ of 



male Spiders was discovered by Menge (" Ueber die Lebensweise 



