472 THE PALEONTOLOGY OF MINNESOTA. 
LKampylopegmata. 
plates of the dorsal valve do not converge medially and join with the posterior end 
of the median septum, as in Magellania, but that they probably coalesce with each 
other; a median septum is not present. Muscular scars undetermined. Shell 
structure impunctate, distinctly fibrous. 
Named for the veteran paleontologist of the New York survey, whose "courtesy 
has enabled us to enhance greatly the scientific value of this volume. 
Type: Hallina saffordi W. and S. 
Waldheimia hicarinata Angelin, sp., and W. mawii Davidson* of Upper Silurian 
strata of Gotland and England, in all probability also belong to Hallina. Terehratula 
melonica Barrandef seems to be another species of this genus. The loops of these 
three species are like those in Hallina nicolleti and H. saffordi, but we are not posi- 
tive that all have an impunctate shell structure except W. hicarinata, of which alone 
we have specimens for comparison, and are unable to detect any punctse in them. 
Hallina is the earliest loop-bearing genus known, and since it is chronotogeneti- 
cally probably near the stock in which the loop and spire-bearing genera had their 
origin (the Rhynchonellidce) it is safe to say that its calcareous brachial supports do 
not pass through any metamorphoses as in the Terebratellid((\ The fundamental 
difference between the familiies Terehratulida^ and Terebratellidfe is not that the former 
have short loops and the latter long ones, but that the first develops its various 
generic types of calcareous brachial supports direct, while in the Terehratellidw the 
mature form is attained by a series of changes or metamophoses. The value of 
these differences as characters of first importance for family distinction was first 
announced by Deslongchamps.:|: The recent work of Fischer and Q^hlert§ on antarctic 
living Terehratellidce emphasizes this difference in the development of the loop-bearing 
forms still more.Jl While Hallina has a long loop, in most respects like mature 
Magellania, it cannot be associated with the latter for the above given reasons, but 
must be referred to the family Terehratellidce. Hallina has its nearest relatives in 
Cryptonella, Hall and Megalanteris (Meganteris), Suess of the Devonian. The former 
can be distingushed from Hallina by its punctate shell structure and the anomalous 
band joining the crural plates on the dorsal side, while Megalanteris differs from both 
in the long anteriorly-directed prongs of the crura. It is upon these three genera 
that Beecher will establish the subfamily Cryptonellinre. 
If the loop-bearing families {Terehratulida' and Terehratellidce) had their origin 
in the Rhynchonellidce, which seems probable since the greater portion of the genera 
of that family are rostrate in form and with more or less completely developed 
♦British Silurian Bracb., vol. v, pt. i, p. 76, 1882. 
+ See Hall's illustrations of this species in Sixteenth Rep. State Cab. Nat. Hist., p. 49, 1863. 
t Etudes Critiques sur des Brachiopodes Nouveau.x ou peu connus, fasc. 4, 5, 6, pp. 153 and 161, 1884. 
§ Mission Scientifique du Cap Horn, Brachiopodes. Ext. Bull. Soc. d' Hist. Nat. d' Autun, t. v, 1892. 
II We will not enter into further remarks on this point, since Dr. C. E Beecher has in press a revision of these families. 
