120 THE VOYAGE OF H.M.S. CHALLENGER. 
corallum is very common among these forms owing to the fact that the members are un- 
attached except in their very young stages—Podabacia excepted. Such injury and 
consequent reparation are frequently met with in Fungia, Halonitra, Herpetolitha, and 
Lithactinia, and oceasionally in Podabacia and Cryptabacia; though the thickness of 
the corallum in the larger number of cases would prevent the fracture giving rise to 
many pieces, and hence the growth resulting from injury in these forms would 
seldom, if ever, present the complicated arrangement found in the repaired forms of 
Cycloseris. 
According to the size and shape of the fragment, would be the shape and relative 
size of the different parts of a repaired form. If the specimen broken be quite small, its 
adult repaired form, though showing the lines of fracture or interrupted growth, will 
take on most closely the circular shape of the perfect specimen, and such forms as these 
are extremely common in the Cycloseris distorta and Cycloseris freycineti. When the 
fracture occurs in specimens that are larger, but yet not adult, the adult repaired speci- 
men presents marked inequality between the older and the later growth on the two sides ; 
and this condition is again extremely common among specimens of the above species. 
Complication of parts may arise in both of these cases, by additional or subsequent 
fracture in the repaired specimen. A very common condition met with is that in which 
smaller or larger pieces are found, in which reparation has not yet taken place or has 
just begun, the new growth in the later case being found almost invariably to be in a 
direction at right angles to the line of fracture of the specimen along the whole course of 
this line. If the specimens broken be large this condition persists in the repaired 
form; if the specimens be small it becomes much altered in the course of growth, 
the septa becoming inclined at a gradually lessening angle along the original lines of 
fracture. 
In a large series of specimens of Cycloseris distorta and Cycloseris freycineti, it is 
easy to recognise the various steps as above described, which force one to the only 
explanation that is possible of their origin and development. 
Six species of the genus were obtained. 
1. Cycloseris distorta (Michelin). 
Fungia distorta, Michelin, Mag. de Zool., v. (Zooph.), pl. v., 1843. 
Diaseris distorta, Milne-Edwards and Haime, Cor., iii. p. 55, pl. D. 12, fig. 4. 
3 - Semper, Zeitschr. f. wiss. Zool., Leipzig, xxii. pl. xxi. fig. 2. 
Two pieces of separate specimens were obtained, one of which is about 5 cm. in 
diameter. 
Locality. Santa Cruz Major Island, off Samboangan, Philippines, 10 fathoms. 
