12 
K. L. Prendergast. 
Leptalosia, Strophalosia^ Productella, Gigantella and Productma Sutton. 
The remaining Productid genera of the Mississippian rocks are grouped as 
the Productinae and possess in common a ‘darge and medium to deep visceral 
cavity — Frederick’s Productus typici cc P 
This cannot be regarded as a biological or palaeontological classification; 
it is as Sutton (p. 538) says, ^‘a classification by which different forms may 
be recognised,” in other words, a key, and a key only for the Mississippian 
Productidae. Sutton supports this ‘^classification” by reference to one now 
being worked out by Stoyanow, who is using as a diagnostic feature the 
character of the cardinal process, whether trifid or bifid. Examination of 
the Australian Productids shows that all have essentially the same type of 
cardinal process, but Stoyanow will doubtless define his terms more accur- 
ately when his paper is published. 
In the classitication which follows the author has tried to group closely 
related forms together, and finds that in so doing he has reverted largely to 
AYaagen’s original diagnoses of the sub-families while following Licharew in 
the definition of the Productidae. 
Family Productidae Gray 1840. Synopsis of the contents of the British 
l\rusemn. 42nd Edition, p. 151. 
Shells free, a+tached hy spines or cemented directly by pedicle valve. 
Cardinal margin straight. Surface ornamentation of spines over whole or part 
of shell. Brachial valve with reniform brachial impressions and median septum. 
Cardinal process prominent. 
Sub-family 1. CltonefiTiae Waagen 1884. Salt Range Fossils, I. Productus- 
Limostone Fossils: TV (fasc. 3) Brachiopoda, Pal. Ind. Ser. XIII, p. 612. 
Productids with large spines only along cardinal margin of pedicle valve. 
Cardinal area and teeth in })edicle valve. Muscle impressions non-dendritic. 
Genera. Chonctea sensu lato. 
Chonopectus. 
Daviesiella. 
Sub-family 2. Productinae Waagen 1884, op. cit., pp. 612, 613. Productids 
with dentritic muscle impressions and without teeth. Hollow spines present 
over whole or part of shell. 
Genera. Productus sensu lato. 
Productella. 
Aidosteges. 
Sub-family 3. Slrophalodinae Schuchert 1913, in Zittel K., Textbook of 
Palaeontology edited by C. R. Eastman, 2nd edition p. 391. 
Productids attached by spines and by part or whole of the pedicle valve. 
Ornamentation usually spinose. Muscle impressions non-dentritic. Pedicle valve 
with cardinal area and teeth. 
( Jenus. Strophalosia. 
Heteralosia. 
V. DESCKIPTION OF SPECIES. 
DICTYOCLOSTUS Muir-Wood emend. 
1930. Muir-Wood, A7in. Mag. Nat. Hist. (10) Y p. 103. 
GeU'C-type. — Original designation. Ano^nites semireticulatus Martin (in part). 
Petrifacta Derl)iensia, Wigan 1909, p. 7, pi. xxxii, figs. 1, 2; pi. xxxiii, fig. 4. 
Diagnosis . — Shell elongate or quadrate in outline, hinge wide; ginglymus 
may be present. Pedicle valve convex or geniculate ; visceral disc with semi- 
reticulate ornamentation; trail costatc, costae may bear spines both on trail 
